Dissertations / Theses on the topic 'Packaging and refrigerated storage'
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1
Bruas-Reignier, Françoise. "Relations entre conditions de production, composition chimique et évolution post-mortem des viandes de jeunes bovins." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL041N.
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Afin de mieux connaitre les effets de la maturation sur les viandes de jeunes bovins laitiers abattus dans un abattoir industriel, ont été étudiées l'évolution de la composition chimique et de la structure myofibrillaire de muscles soumis à une conservation sous vide à 4°C jusqu'à 14 jours post-mortem. La variabilité entre les muscles Longissimus dorsi (LD), Triceps brachii caput longum (TBCL) et Rectus femoris (RF), et la variabilité entre individus ont été étudiées. L’influence de facteurs zootechniques a été abordée. Dans un premier essai, 13 animaux ont été étudiés. Les teneurs en eau et en azote total n'évoluent pas au cours de la conservation. L’azote non protéique (ANP) augmente. La teneur en azote protéique soluble (APS) augmente entre 3 et 7 jours puis chute jusqu'à 14 jours. L’index de fragmentation myofibrillaire (IFM) augmente avec un pallier atteint vers 7 jours post-mortem. Les variations de l'ANP, l'IFM et l'APS ne sont pas corrélées. La composition chimique n'influe pas sur le développement de la maturation. La variation d'ANP est liée au poids de carcasse. Dans un deuxième essai, les relations entre composition chimique, structure, protéolyse et état de maturation ont été étudiées sur le muscle LD de 32 animaux issus de 5 élevages. La composition chimique, l'IFM, la longueur de sarcomères sont liés aux caractéristiques des animaux. Une discrimination des 5 élevages par la composition chimique du LD, les caractéristiques des carcasses et la différence entre les valeurs de force de compression à 20% à 10 et 3 jours est mise en évidence. L’état de maturation est très variable entre individus à 3 jours, mais semble atteindre une même valeur seuil à 10 jours. Les estimateurs de protéolyse, de fragmentation et de maturation ne sont pas liés et sont indépendants de la composition chimique. Dans un troisième essai, les relations entre cinétiques de chute de pH post-mortem ont été abordées sur 6 individus de l'essai 1 et 9 de l'essai 2. La vitesse et l'amplitude de chute du pH ne sont pas liées aux caractéristiques des carcasses. Les modèles de prévision établis montrent que la maturation est liée aux caractéristiques des animaux (poids et âge) et de façon moins nette aux conditions d'entrée en rigor.
2
Blanchard, Jacquelyn. "Simulation of Refrigerated Food Quality during Storage and Distribution." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587045898641609.
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Ben, Abdallah Mheni 1963. "Some factors influencing myoglobin derivatives on refrigerated packaged beef." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278237.
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The effects of microbial growth, packaging film permeability, and freezing on the discoloration of beef was assessed by measuring myoglobin derivatives and specifically the rate of formation of metmyoglobin on the surface of Longissimus dorsi and Semimembranosus bovine muscles during 12 days of storage at 2°C. Frozen thawed sterile beef samples experienced higher metmyoglobin formation than fresh sterile beef samples. By day 2, up to 20% metmyoglobin was formed in the thawed samples whereas, the fresh samples reached this value after day 6. After 6 days, the growth of Pseudomonas florescence had a significant effect on myoglobin oxidation and this behavior continued for the remaining period of the storage. Gas barrier film and gas permeable film exhibited similar results at day 0 and day 3 of storage, however at day 6 of storage, samples packaged with the gas barrier film showed metmyoglobin percentage significantly higher that those packaged with gas permeable film. (Abstract shortened by UMI.)
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Rheinhart, Courtney Elizabeth. "Clostridium botulinum toxin development in refrigerated reduced oxygen packaged Atlantic croaker (Micropogonias undulatus)." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/32440.
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The purpose of this study was to determine the effects of storage temperature and film oxygen transmission rate (OTR) on toxin development by Clostridium botulinum in refrigerated raw vacuum packaged croaker fillets, and to determine if toxin development precedes microbiological and/or organoleptic spoilage. Raw croaker fillets were vacuum packaged in oxygen-permeable films (OTR of 10,000 cc/m2/24hr or 3,000 cc/m2/24hr) and stored at either 4ºC or 10ºC. Type 83F, 17 Type B, Beluga, Minnesota, and Alaska nonproteolytic strains of C. botulinum were used to inoculate fish prior to vacuum packaging. At both temperatures, microbial spoilage preceded toxin production in fillets vacuum packaged in both film types. At 4ºC microbial spoilage occurred after approximately 7 days for fillets vacuum packaged in the 10,000 cc/m2/24hr OTR film and after 8 days for fillets vacuum packaged in the 3,000 cc/m2/24hr OTR film. However, toxin was not detected until day 8. At 10ºC microbial spoilage occurred after approximately 3 days for fillets vacuum packaged in the 10,000 cc/m2/24hr OTR film, while toxin production occurred on day 5. For fillets vacuum packaged in the 3,000 cc/m2/24hr OTR film microbial spoilage occurred after 4 days. However toxin production did not occur until day 6. In contrast, at both temperatures toxin production preceded or coincided with organoleptic spoilage in fillets vacuum packaged in both film types. At 4ºC organoleptic spoilage occurred after 10 days for fillets packaged in the 10,000 cc/m2/24hr OTR film and after 9 days in the 3,000 cc/m2/24hr OTR film, while toxin production occurred on day 8. At 10ºC organoleptic spoilage occurred after 6 days for fillets packaged in the 10,000 cc/m2/24hr OTR film, and toxin was detected on day 5. For fillets packaged in the 3,000 cc/m2/24hr OTR film and stored at 10ºC, organoleptic spoilage occurred after 6 days, while toxin production occurred on day 6. Although toxin production preceded or coincided with organoleptic spoilage in both film types, this may have been because samples were presented on ice, which could have masked potential odors. This study shows that there are not significant differences between these film types when it comes to microbial and organoleptic spoilage. Therefore lower OTR films, such as 3,000 cc/m2/24hr film, may be used to vacuum package Atlantic croaker.Master of Science in Life Sciences
5
Ahn, Insook. "The effect of modified atmosphere packaging (MAP) on the shelf- life of refrigerated, cubed turkey thigh meat." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-08182009-040248/.
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Simpson, Marian V. "Shelf life and microbiological safety studies on minimally processed, refrigerated "sous-vide" products." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41134.
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Previous results indicated that lactic acid bacteria (LAB) and Bacillus spores were the predominant spoilage microorganisms in minimally processed products after 35 days storage at 15$ sp circ$C. Furthermore, most packages were swollen due to carbon dioxide production by the LAB. The fact that spores survived mild heat treatment is of concern since it implies that other more pathogenic spores, e.g. Clostridium botulinum would also survive and may pose a public health problem in products stored at 15$ sp circ$C. As such, the influence of combination treatments (viz., mild heat processing treatment, pH, water activity, storage temperature, lactic acid bacteria) were evaluated through challenge studies with selected strains of C. botulinum type A, B, and E spores. The shelf life and safety of the products following a 13D process at 75$ sp circ$C, could be extended to $ ge$42 days by a combination of pH $ le$ 5.0 and storage at 5$ sp circ$C. Other combination treatments were also effective in controlling growth of, and toxin formation in the products by C. botulinum. For instance, botulinum toxin was not detected until day 35 in inoculated spaghetti and meat sauce products (pH 5.25 and a$ sb{w}$ 0.992) with type A and B spores and stored at 15$ sp circ$C. Shelf life extension and inhibition of toxin production was also possible through reductions in a$ sb{w}$ levels achieved by addition of 1-3% salt (w/w) to the products. Water activity levels of $ le$0.983 prevented botulinum toxin production in the minimally processed spaghetti and meat sauce product for $ ge$42 days during storage at 15$ sp circ$C.Similar trends were observed in sous-vide rice and salmon products. Furthermore, when sodium lactate was used as the humectant to lower the a$ sb{w}$ of this product, toxin production was also delayed, but not to the same extent as achieved with NaCl. When two strains of bacteriocin-producing lactic acid bacteria were co-inoculated separately in the sous-vide rice and salmon products that had been challenged with C. botulinum type E spores, toxin formation was only slightly delayed in products with added NaCl (1%), while toxin formation was neither delayed nor prevented in similarly lactic acid bacteria-treated samples with no added NaCl. Furthermore, in most of the products in which botulinum toxin was detected, spoilage preceded toxigenesis, however, in some samples stored at 5$ sp circ$C toxigenesis preceded spoilage. Addition of $ alpha$-2-macroglobulin at a level of 2.7 ppm did not delay or prevent toxin formation in the product. Microwave heating of products at half-power or full power (800 Watts) for 5 to 10 min proved effective in inactivating all of the pre-formed toxin in toxic samples. (Abstract shortened by UMI.)
7
Piotrowski, Christine Lelia. "Survival of Listeria monocytogenes in Fruit Juices During Refrigerated and Temperature-Abusive Storage." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9619.
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Survival of Listeria monocytogenes in apple, orange, red grape, and white grape juice was evaluated. A six-strain cocktail of L. monocytogenes was used to inoculate (approx. 7 log cfu/ml) fruit juices, which were stored at 4, 10 and 24°C for up to 61 days. Inoculated red grape juice was stored for up to 5 hours only. Samples were withdrawn at appropriate intervals, neutralized with 1.0 N NaOH, serially diluted in 0.1% peptone water, and surface plated onto Tryptic Soy Agar + 0.6% Yeast Extract (TSAYE) and Modified Oxford Agar (MOX), followed by incubation at 32°C for 48 hours. When L. monocytogenes was no longer detected by direct plating, samples were enriched for L. monocytogenes using Listeria Enrichment Broth (LEB), followed by isolation on MOX. L. monocytogenes remained viable in white grape, apple, and orange juices for up to 12, 24 and 61 days, respectively. Over time, recovery of Listeria on TSAYE versus MOX was not significantly different (P>0.05), indicating that limited acid-injury developed during storage. The results of this study demonstrate the ability of L. monocytogenes to survive in apple, orange, and white grape juices during refrigerated and abusive storage conditions. Therefore, measures to prevent or eliminate L. monocytogenes in the fruit juice-processing environment are necessary to ensure the safety of juice products for public consumption.Master of Science
8
Huskey, Mariah A., Paul O. Lewis, and Stacy D. Brown. "Stability of Ampicillin in Normal Saline Following Refrigerated Storage and 24-hour Pump Recirculation." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/asrf/2020/presentations/8.
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Purpose: Use of ampicillin in outpatient parenteral antimicrobial therapy (OPAT) has historically been complicated by frequent dosing and short beyond use dates. However historic stability data relied on inaccurate testing methods. The purpose of this study is to evaluate the stability of ampicillin using high-pressure liquid chromatography (HPLC), the gold standard, in a real-world OPAT dosing model using continuous infusion at room temperature over 24 hours immediately following preparation compared to batches stored under refrigeration for 24 hours, 72 hours, and 7 days.
Methods: An HPLC method was developed and validated as stability – indicating according to guidance in USP general Chapter . Method development included linearity, precision, accuracy, repeatability and forced degradation. Four batches were prepared using 4 different lots from 2 different manufacturers for each storage condition (immediate, 24 hours, 72 hours, and 7 days). Three 2-gram vials were each reconstituted with 10 mL of sterile water for injection (SWFI) and added to 250 mL of normal saline by a licensed pharmacist and stored in a laboratory refrigerator (2 – 8oC). A pump system was used to continuously circulate the solutions through medical grade tubing at room temperature. One milliliter aliquots were removed from each batch at time 0, 4 hours, 8 hours, 12 hours and 24 hours and analyzed for ampicillin concentration using the aforementioned HPLC method. The samples were filtered prior to analysis using a 0.22-micron syringe filter and analyzed in triplicates along with freshly prepared calibration samples (24 – 12 mg/mL). Peak area was used to determine percent recovery for each sample.
Results: Each batch was assayed for initial concentration (20.34 – 21.50 mg/mL) upon preparation, and percent recovery was compared to that initial concentration thereafter. Acceptable recovery was defined as 90 – 110% of initial concentration. On the day of product preparation (immediate use), the average percent recovery over 24 hours was 96.4%. The other average percent recoveries were as follows: 95.8% (24-hour storage), 94.6% (72-hour storage) and 90.3% (7-day storage). These data represent the average percent recovery for all time points during the 24 hours sampling (n = 60 for each experiment). When evaluating individual time points, the percent recovery remained above 90% for all batches and time points except for the 7-day storage experiment. Under 7-day storage conditions, the percent recovery fell below 90% after 4 hours of circulation through the medical grade tubing. Furthermore, 95% confidence interval for percent recovery for ampicillin in the samples stayed within 90 – 110% of the initial concentration for the duration of the experiment for all test groups except 7-day storage.
Conclusions and Relevance: Ampicillin can be prepared and stored in a refrigerator for up to 72-hours prior to continuously infusing at room temperature over 24 hours with less than a 10% loss of potency over the dosing period. This model supports twice weekly OPAT delivery of ampicillin.
9
Huskey, Mariah, Paul O. Lewis, and Stacy Brown. "Stability of Ampicillin in Normal Saline Following Refrigerated Storage and 24-Hour Pump Recirculation." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/7844.
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Purpose: Use of ampicillin in outpatient parenteral antimicrobial therapy (OPAT) has historically been complicated by frequent dosing and short beyond use dates. However historic stability data relied on inaccurate testing methods. The purpose of this study is to evaluate the stability of ampicillin using high-pressure liquid chromatography (HPLC), the gold standard, in a real-world OPAT dosing model using continuous infusion at room temperature over 24 hours immediately following preparation compared to batches stored under refrigeration for 24 hours, 72 hours, and 7 days.
Methods: An HPLC method was developed and validated as stability – indicating according to guidance in USP general Chapter < 1225 >. Method development included linearity, precision, accuracy, repeatability and forced degradation. Four batches were prepared using 4 different lots from 2 different manufacturers for each storage condition (immediate, 24 hours, 72 hours, and 7 days). Three 2-gram vials were each reconstituted with 10 mL of sterile water for injection (SWFI) and added to 250 mL of normal saline by a licensed pharmacist and stored in a laboratory refrigerator (2 – 8oC). A pump system was used to continuously circulate the solutions through medical grade tubing at room temperature. One milliliter aliquots were removed from each batch at time 0, 4 hours, 8 hours, 12 hours and 24 hours and analyzed for ampicillin concentration using the aforementioned HPLC method. The samples were filtered prior to analysis using a 0.22-micron syringe filter and analyzed in triplicates along with freshly prepared calibration samples (24 – 12 mg/mL). Peak area was used to determine percent recovery for each sample.
Results:Each batch was assayed for initial concentration (20.34 – 21.50 mg/mL) upon preparation, and percent recovery was compared to that initial concentration thereafter. Acceptable recovery was defined as 90 – 110% of initial concentration. On the day of product preparation (immediate use), the average percent recovery over 24 hours was 96.4%. The other average percent recoveries were as follows: 95.8% (24-hour storage), 94.6% (72-hour storage) and 90.3% (7-day storage). These data represent the average percent recovery for all time points during the 24 hours sampling (n = 60 for each experiment). When evaluating individual time points, the percent recovery remained above 90% for all batches and time points except for the 7-day storage experiment. Under 7-day storage conditions, the percent recovery fell below 90% after 4 hours of circulation through the medical grade tubing. Furthermore, 95% confidence interval for percent recovery for ampicillin in the samples stayed within 90 – 110% of the initial concentration for the duration of the experiment for all test groups except 7-day storage.
Conclusion:Ampicillin can be prepared and stored in a refrigerator for up to 72-hours prior to continuously infusing at room temperature over 24 hours with less than a 10% loss of potency over the dosing period. This model supports twice weekly OPAT delivery of ampicillin.
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Choucha, Sam E. "Color and shelf-life studies of fresh beef packaged in various gas atmospheres and stored at refrigerated temperature." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0024/MQ37108.pdf.
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Thompson, V. "Structural integrity of liquid natural gas storage tanks." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371581.
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Amaral, Andre Renato Sales. "Solution methods for cutting and packaging problems." Thesis, Lancaster University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322072.
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Brown, Stacy, Jessica Huffman, Amanda Ogle, and Paul Lewis. "Stability of Compounded Pyrimethamine Oral Suspension Stored at Room and Refrigerated Temperature." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/5270.
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Day, Ngoc Bich. "The inhibition of yeast spoilage of blueberries during modified atmosphere packaging storage." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27868.
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Modified atmosphere packaging storage combines an atmosphere of higher carbon dioxide and lower oxygen levels than air, with chilling temperatures to extend shelf-life of fresh fruits.
In three modified atmosphere packaging storage trials, blueberries were packaged in film bags with different gas permeabilities, and stored at about 4°C. Storage of blueberries in packages of a film with intermediate gas permeability produced an aerobic atmosphere and a relatively low carbon dioxide level, resulting in rapid growth of yeast and molds on blueberries. Packaging blueberries in a film with very low gas permeability created a high carbon dioxide almost anaerobic atmosphere, which successfully inhibited yeast and mold growth on blueberries for up to eight weeks.
The possibility of yeast inhibition by antifungal compounds accumulated in blueberries stored under modified atmosphere packaging conditions was investigated by using the disk diffusion assay. The results of these assays showed the absence of antifungal activity against two Rhodotorula species, a Zygosaccharomyces species, a Cryptococcus species, a Debaryomyces species, and indicated that the inhibition of yeast growth was due to low temperature, high carbon dioxide level and anaerobic conditions. The effects of temperature and atmosphere composition were investigated by using natural flora of blueberry juice and two yeast isolates grown in sterilized juice. At 21°C, yeast growth was slow in the presence of carbon dioxide and absence of oxygen. At low temperature, yeast growth was slow in the presence of oxygen, but was inhibited in the anaerobic, high carbon dioxide environment.
It is proposed that the micro-aerobic environment of modified atmosphere packaging storage might have allowed slow desaturation of yeast membrane fatty acids which enabled yeasts to maintain membrane fluidity and function at low .temperature. Furthermore, yeast growth during storage of modified atmosphere packaged blueberries may be affected by low temperature and high carbon dioxide conditions.Land and Food Systems, Faculty of
Graduate
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Subbiah, Jeyamkondan. "Design and evaluation of a portable, nitrogen-refrigerated, jacketed container for storage and distribution of chilled meat." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0001/MQ41783.pdf.
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Zhang, Wangang. "Involvement of protein degradation, calpain autolysis and protein nitrosylation in fresh meat quality during early postmortem refrigerated storage." [Ames, Iowa : Iowa State University], 2009.
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Ford, Tara K. "Interaction of non-meat ingredients on sensory characteristics and chemical characteristics of pork loin chops during vacuum-packaged refrigerated storage." Texas A&M University, 2004. http://hdl.handle.net/1969.1/2687.
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Fresh, boneless, vacuum-packaged pork loins were obtained from a
commercial pork processor and used in a five-part study to examine the effects
of sodium chloride (0, .125, .375, .75, 1.50%), sodium phosphates (0, .1, .2, .3
and .4%), sodium lactate (0, 1, 2, 3 and 4%), potassium lactate (0, 1, 2, 3 and
4%) and sodium diacetate (0, .05, .10, .15 and .20%) on the color, sensory
characteristics, package purge, water holding capacity, and pH of pork chops
stored in vacuum-packaging for 0, 7, 14, 21 and 28 days. The first experiment
examined the effects of sodium chloride and sodium phosphates (Brifisol 512,
polyphosphate blend) in the aforemented attributes. The second experiment
was designed like the first experiment except a different sodium phosphate
(Brifisol 85, polyphosphate and pyrophosphate blend) was used. In the third
experiment, sodium chloride was standardized at .75% and sodium phosphate
and sodium lactate differed. In the fourth experiment, sodium chloride was
standardized at .75% and sodium phosphate and potassium lactate differed. In
the fifth experiment, sodium chloride and potassium lactate were standardized at
.75% and 2%, respectively, and sodium phosphate and sodium diacetate
differed. Results from Experiments 1 and 2 indicated that pork chops should
contain .2% NaP + .75% NaCl to improve flavor, texture, and water holding
capacity over storage time. Based on results from Experiments 3 and 4, it is
recommended that pork chops contain approximately 2% NaL or KL + .2% NaP
to maintain positive sensory flavor, texture, color and minimize processed meatlike
bite, package purge, and cook loss over time. The combination of
approximately .1% NaDi + .2% NaP maximized desirable characteristics like
pork lean/brothy, juiciness, tenderness, and color; and minimized processed
meat-like bite when compared to the control chops in Experiment 5.
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Carr, Joel Matthew. "CONFINED LAYERED POLYMERIC SYSTEMS FOR PACKAGING ANDCAPACITOR APPLICATIONS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=case1363104386.
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Huffman, Jessica, Stacy D. Brown, Paul O. Lewis, Sarah Lawson, Amanda P. Ogle, and Gina Peacock. "Comparative Stability of Oral Vitamin K Liquids Stored in Refrigerated Amber Plastic Syringes." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5323.
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The purpose of this study was to evaluate the stability of vitamin K1 oral liquids in Sterile Water for Injection when stored in amber glass bottles and amber plastic syringes under refrigerated conditions. Four 100-mL batches of vitamin K1 in Sterile Water for Injection were prepared in amber glass bottles to protect from light. One of the batches was divided into 1-mL aliquots, using amber plastic oral syringes, and capped. The prepared bottles and syringes were stored in a laboratory refrigerator. On each day of sampling, 1-mL aliquots were removed from each bottle and mixed with an equal volume of ethanol. Likewise, the contents of sample syringes were mixed with ethanol to achieve an assay concentration of 0.5 mg/mL. Recovery of vitamin K1 in the compounded samples was quantified against a United States Pharmacopeia reference standard. Quantification was achieved using a stability-indicating high-performance liquid chromatography with ultraviolent light detection method. Product stability is defined as 90% to 110% of the initial concentration. The percent recovery in the Sterile Water for Injection preparations in glass bottles remained above 90% for the 105-day duration of the study, but some samples stored in amber plastic syringes fell below 90% on day 21. Furthermore, a statistically significant difference (2-way ANOVA, P < 0.0001) emerged between syringes at day 0 and day 30, and this trend continued through the day 60, 90, and 105 samples. The only statistically significant difference found within the bottle-stored samples occurred on day 105 (versus zero, P = 0.0465), but the recovery on day 105 still exceeded 90%. Vitamin K1 in Sterile Water for Injection, stored in a refrigerated amber glass bottle, is stable for 105 days. This preparation can also be stored in amber plastic syringes, but this decreases the beyond-use date to 14 days.
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Carr, Timothy Perry. "EFFECT OF CONTROLLED GAS ATMOSPHERE PACKAGING UPON THE STORAGE QUALITY OF PRECOOKED BEEF SLICES." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275255.
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Eshpari, Hadi. "EVALUATION OF VACUUM PACKAGING ON THE PHYSICAL PROPERTIES, SOLUBILITY, AND STORAGE SPACE OF DAIRY POWDERS." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/604.
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As many of the dairy powders manufactured have to travel long distances to reach their customers, both domestically and internationally, there is considerable interest among dairy powder manufacturers to maintain the quality of their products for relatively long storage periods. Dairy powders can have a long shelf life if packaged and stored properly. Vacuum packaging can be an attractive packaging strategy to maintain the quality of dairy powders and provide added value by improving the efficiency of using the storage space; because of the inherent compactness of these products. Vacuum packaged dry dairy ingredients may also have added ease of handling for end users. However, little is known about the impact of vacuum packaging on the physical properties of dry dairy ingredients. The main objective of this study was to determine the effect of vacuum packaging over 12 months storage on particle size, particle density, bulk density, tapped density, flowability, compressibility, color, moisture content, surface morphology, and solubility of six types of dairy powders. In addition, the effect of dairy ingredients type was also assessed. Commercial samples of nonfat dry milk powder, whole milk powder, buttermilk powder, milk protein Isolate, whey protein concentrate#80, and sweet whey powder were repackaged in duplicate using multi-wall foil side gusseted bags under varying degrees of vacuum (1, 0.7, 0.4 bar) and a control with no vacuum, then stored for 3, 6, and 12 months at 25°C and 60% relative humidity. Each powder was sampled and analyzed in duplicate for all the above listed quality attributes, upon receiving the powder and after 3, 6, and 12 months of storage.
Moreover, the effect of vacuum packaging on storage space was evaluated comparing three different models; Model (1) represented a 25 kg bag of atmospheric packaged non fat dry milk with the actual dimensions of a commercial 25 kg bag of non fat dry milk. Model (2), a hypothetical model, represented a 25 kg bag of vacuum packaged non fat dry milk with a length and a width equal to those of model (1). Model (3), another hypothetical model, also represented a 25 kg bag of vacuum packaged non fat dry milk with a length equal to half of a pallet width and a width equal to one third of a pallet length, in order to achieve the highest pallet efficiency possible. The pallet used for all three models was considered to be a (48 × 40) pallet. The height of models 2 and 3 was allowed to reflect the bulk reduction effect of vacuum packaging and was determined based on the weight, density and the known dimensions of the bags. It is important to note that the density of models 2 and 3 was assumed to be equal to the density of a small bag of nonfat dry milk. The saved space per bag and pallet efficiency of vacuum packaging and atmospheric packaging were compared using the three models described above.
Physical properties analyses of the dairy powders revealed statistically significant effect of vacuum pressure on only color values: L-, a-, and b but none of the other powder quality attributes examined. Powders packaged under vacuum showed a significantly higher mean of L- color value (p-value = 0.003 < 0.01), but significantly lower means of (a- and b-) color values (p-values = 0.005, and 0.001, respectively). This effect was more dramatic in high fat containing powder such as whole milk powder. In fact, vacuum packaged whole milk powders were significantly whiter, less red, and less yellow. It is likely that vacuum packaging has prevented color changes due to lipid oxidation in whole milk powder.
Physical properties analyses of the dairy powders also revealed statistically significant increases in the particle density, particle size, bulk density, and tapped density due to the effect of storage time (all p-values = 0.000 < 0.01), statistically significant decreases in the angle of repose and compressibility due to the effect of storage time (p = 0.000 < 0.01) and (p = 0.004 < 0.01), respectively. The physical properties analyses also revealed a statistically significant effect of the powder type on particle density, particle size, bulk density, and tapped density, angle of repose, compressibility, and color values: L-, a-, and b- (all p-values = 0.000 < 0.01). In other words, particle density, particle size, bulk density, and tapped density of the powders increased over the storage time, while angle of repose (AOR) and compressibility decreased over the storage time. The powder type had a significant effect on particle density, particle size, bulk density, tapped density, AOR, compressibility, and color values: L-, a-, and b; however, it did not have any significant effect on solubility and moisture content.
In addition, observations of the surface morphology of dairy powders were made using a scanning electron microscope. This evaluation demonstrated the differences in powder particle shape and surface morphology which are believed to be partially responsible for the significant differences observed in the physical properties, due to the effect of powder type.
It was shown that vacuum packaging does increase the efficiency of using the storage space by removing the interstitial air and increasing the density of the powder. As described above, the height of model (2) and the length of model (3) both were expectedly shorter compared to those of model (1). Storage space calculations for non fat dry milk were performed based on comparing the volume of the 3 models and showed 15 % saving in storage space per bag and per pallet, due to vacuum packaging. The effect of space saving on the number of bags per pallet was evaluated using CAPE PACK v2.09 software and showed an increase from 45 bags/ pallet in model (1) to 50 bags/ pallet in model (2) and 54 bags/ pallet in model (3).
Overall, this study demonstrates the impact of vacuum packaging on physical properties, solubility, and storage properties of dairy powders. The data suggest that the proposed vacuum packaging method may be beneficial to maintain the quality of the powders studied and it results in space savings per unit of dairy powder compared to conventional atmospheric packaging.
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Dehghannya, Jalal. "Mathematical modeling of airflow, heat and mass transfer during forced convection cooling of produce in ventilated packages." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115663.
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Forced convection cooling process is the most widely used method of cooling to extend shelf life of horticultural produce after harvest. However, heterogeneous cooling of produce inside different parts of ventilated packages is a serious problem. Therefore, it is essential to design packages that facilitate air circulation throughout the entire package to provide uniform cooling. Selection of appropriate combinations of air temperature and velocity for a given vent design is currently done largely by experimental trial and error approach. A more logical approach in designing new packages, to provide uniform cooling, is to develop mathematical models that would be able to predict package performance without requiring costly experiments.In this study, mathematical models of simultaneous airflow, heat and mass transfer during forced convection cooling process were developed and validated with experimental data. The study showed that produce cooling is strongly influenced by different ventilated package designs. Generally, cooling uniformity was increased by increasing number of vents from 1 (2.4% vent area) to 5 (12.1% vent area). More uniform produce cooling was obtained at less cooling time when vents were uniformly distributed on package walls with at least 4.8% opening areas. Aerodynamic studies showed that heterogeneity of airflow distribution during the process is strongly influenced by different package vent configurations. The highest cooling heterogeneity index (108%) was recorded at 2.4% vent area whereas lowest heterogeneity index (0%) was detected in a package with 12.1% vent area.
The magnitudes of produce evaporative cooling (EC) and heat generation by respiration (HG) as well as the interactive effects of EC, HG and package vent design on produce cooling time were also investigated. Considerable differences in cooling times were obtained with regard to independent and simultaneous effects of EC and HG in different package vent configurations. Cooling time was increased to about 47% in a package with 1 vent compared to packages with 3 and 5 vents considering simultaneous effects of EC and HG. Therefore, the effects of EC and HG can be influential in designing the forced-air precooling system and consequently, in the accurate determination of cooling time and the corresponding refrigeration load.
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Uchechukwu-Agua, Amarachi Divine. "Effects of packaging and storage condition on functional properties and quality attributes of cassava flour (CVS. ‘TME 419’ AND ‘UMUCASS 36’)." Thesis, Stellenbosch : Stellenbosch University, 2015, 2015. http://hdl.handle.net/10019.1/97142.
Full textAbstract:
Thesis (MSc Food Sc)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Cassava flour is recommended for substitution with wheat flour in composite flour for baking. The potential use of cassava flour in the food and pharmaceutical industries is attributed to its gluten-free nature and excellent functional properties. However, optimum packaging solution and storage conditions for cassava flour is critical in maintaining the quality attributes and shelf-life stability during storage. Therefore, this study focused on investigating the effects of package types (plastic buckets, low density polyethylene (LDPE) bags and brown paper bags) and storage conditions (cool condition (15 °C, 90% RH); ambient condition (23 °C, 60% RH); and higher condition (38 °C, 60% RH)) on the functional properties, quality attributes and shelf-life stability of cassava flour (cvs. ‘TME 419’ and ‘UMUCASS 36’) developed at the National Root Crops Research Institute, Umudike, Nigeria. Proximate composition, physicochemical attributes, functional properties, and microbial safety of flour were analysed every 4 weeks for 12 weeks storage duration. Flour stored under cool condition with paper bags became moist and sticky with appearance of mould growth before 4 weeks of storage. However, at the end of 12 weeks storage, a decline in moisture content of 11.00 ± 0.02 and 7.05 ± 0.01% flour of ‘TME 419’ was observed at ambient and higher conditions, respectively. Rate of moisture decline was similar in flour of ‘UMUCASS 36’. A slight decrease in protein content of flour was observed during the 12 weeks storage from 1.9 ± 0.07 to 1.30 ± 0.001% for cv. ‘TME 419’ and 3.0 ± 0.05 to 2.27 ± 0.001% for cv. ‘UMUCASS 36’; however, no significant difference was observed under ambient and higher conditions. Cassava flour packed in paper bags and stored under higher condition (38 °C, 60%) had the highest loss (50%) of carotenoid content from 1.84 ± 0.10% to 0.91 ± 0.08%, while a minimal loss (24%) of carotenoid was observed in flour packed in plastic buckets under ambient condition. The concentration of hydrogen cyanide (HCN) decreased across all treatments and was below the safe cyanide level of 50 µg/ mL for food products. After the 12 weeks of storage, flour packed in plastic buckets had the highest aerobic mesophilic bacterial counts (3.43 ± 0.04 log cfu/ g) followed by flour in LDPE bags (3.37 ± 0.03 log cfu/ g) and paper bags (3.35 ± 0.01 log cfu/ g). No significant difference was observed in the package types; however the counts observed were within the acceptable microbial limit Swelling power (SP), solubility and peak viscosity were used to characterise the changes in functional and pasting properties of cassava flour relevant in food industries. Flour packed in plastic buckets under ambient condition had the lowest swelling power (8.48 ± 0.55%) and peak viscosity (260 ± 0.51 RVU) compared to flour packed in LDPE and paper bags with (9.10 ± 0.13 and 9.32 ± 0.41%) SP and (263.67 ± 4.04 RVU and 302 ± 9.52 RVU) peak viscosity, respectively. The essential minerals (sodium, potassium, copper, and iron) were significantly higher in flour of ‘TME 419’ compared to ‘UMUCASS 36’. In summary, for the production of high grade foods such as bread where higher swelling power and viscosities are required, flour from ‘TME 419’ packed with paper bags under higher condition could be desirable. In addition, for infant formulation, flour from ‘UMUCASS 36’ packed in plastic buckets and stored under ambient condition which best maintained nutritional contents (protein and fat) and had the lowest peak viscosity would be more suitable. Flour from both cassava cultivars could be stored up to 12 weeks duration under ambient and hot tropical conditions using all package types evaluated. However, storage with paper bag under higher condition offers the chances of better shelf -life stability of cassava flour.
AFRIKAANSE OPSOMMING: Daar word aanbeveel dat kassavameel in plaas van koringmeel in saamgestelde meel by gebak gebruik word. Die potensiële gebruik van kassavameel in die kos- en farmaseutiese industrieë word toegeskryf aan die glutenvrye aard en funksionele kenmerke daarvan. Optimale verpakking en stoortoestande is egter belangrik vir die instandhouding van die gehalte kenmerke en raklewe stabiliteit tydens stoor. Daarom is die fokus van hierdie studie op die effek van verskillende tipes verpakking (plastiekemmers, lae densiteits politelien (LDPE) sakke en bruin papiersakke) en stoortoestande (koel toestande (15 °C, 90% RH); omringende temperature (23 °C, 60% RH); en hoër temperature (38 °C, 60% RH) op die funksionele kenmerke, gehalte kenmerke en raklewe stabiliteit van kassavameel (kultivare. ‘TME 419’ en ‘UMUCASS 36’) wat by die Nasionale Wortelgewasse Navorsingsinstituut, Umudike, Nigerië ontwikkel is. Die komposisie, fisiochemiese kenmerke, funksionele kenmerke en mikrobiale veiligheid van meel is elke vier weke tydens die 12-weke stoortydperk ontleed. Meel wat onder koeltoestande in papiersakke gestoor word, word klam en taai en swamme maak by vier weke van stoor ’n verskyning. Teen die einde van 12 weke stoortydperk is daar ’n afname in klammigheid van 11.00 ± 0.02 en 7.05 ± 0.01% in ‘TME 419’ meel by onderskeidelik omgewings- en hoër temperature. Die afname in klammigheid is soortgelyk by ‘UMUCASS 36’ meel. ’n Effense afname in die proteïen inhoud van die meel is tydens die 12- weke stoortydperk vanaf 1.9 ± 0.07 tot 1.30 ± 0.001% by die kultivaar . ‘TME 419’ en 3.0 ± 0.05 tot 2.27 ± 0.001% vir kultivaar ‘UMUCASS 36’ opgemerk. Geen noemenswaardige verskil is egter onder omgewings- en hoër temperature opgemerk nie. Kassavameel wat in papiersakke en onder hoër temperature (38 °C, 60%) gestoor is het die hoogste verlies (50%) aan karotien inhoud vanaf 1.84 ± 0.10% tot 0.91 ± 0.08% getoon , terwyl ’n minimale verlies (24%) by meel wat in plastiekemmers onder omgewingstemperature verpak is, opgemerk is. Die konsentrasie van waterstof hidrosianied (HCN) het tydens alle behandelinge afgeneem en was onder die veilige vlak van 50 µg/ mL vir kosprodukte. Na ’n 12-weke stoortydperk het die meel wat in plastiekemmers verpak is, die hoogste mesofiliese bakterië telling getoon \ (3.43 ± 0.04 log cfu/ g) gevolg deur die meel in die LDPE sakke (3.37 ± 0.03 log cfu/ g) en papiersakke (3.35 ± 0.01 log cfu/ g). Daar was geen merkbare verskil ten opsigte van verpakkingstipes nie; die tellings wat geneem is, was almal binne die aanvaarbare mikrobiale perk. Swelkrag (SP), oplosbaarheid en piek viskositeit is gebruik om die veranderinge in funksionele kenmerke van kassavameel wat betrekking het op die kosindustrie, te ondersoek. Meel wat onder omgewingstemperature in plastiekemmers verpak is, het die laagste swelkrag (8.48 ± 0.55%) en piekviskositeit getoon (260 ± 0.51 RVU) getoon vergeleke met meel wat in LDPE- en papiersakke (9.10 ± 0.13 en 9.32 ± 0.41%) swelkrag en (263.67 ± 4.04 RVU en 302 ± 9.52 RVU) piekviskositeit, onderskeidelik toon. Die belangrike minerale (natrium, kalium, koper en yster) was noemenswaardig hoër in die ‘TME 419’ meel vergeleke met ‘UMUCASS 36’. Ten slotte, vir die produksie van hoëgraad kossoorte soos brood waar hoë swelkrag en viskositeit belangrik is, is In ‘TME 419’ meel onder hoër toestande verpak in papiersakke, die beste keuse. In die geval egter van babakosse is ‘UMUCASS 36’meel wat in plastiekemmers verpak en onder omgewingstemperature gestoor is, en wat dus koswaardes (proteïen en vette) behou en wat die laagste piek viskositeit het, meer geskik. Meel van albei kultivaars kan vir tot twaalf weke onder omgewings- en hoë, tropiese temperature in al die verpakkingstipes wat evalueer is, gestoor word. Stoor in papiersakke onder hoër temperature verbeter egter die kanse op beter raklewe stabiliteit.
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Ngcobo, Mduduzi Elijah Khulekani. "Resistance to airflow and moisture loss of table grapes inside multi-scale packaging." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80192.
Full textAbstract:
Thesis (PhD(Agric))--Stellenbosch University, 2013.ENGLISH ABSTRACT: Postharvest quality of fresh table grapes is usually preserved through cooling using cold air. However, cooling efficiencies are affected by the multi-scale packaging that is commercially used for handling grapes after harvest. There is usually spatial temperature variability of grapes that often results in undesirable quality variations during postharvest handling and marketing. This heterogeneity of grape berry temperature inside multi-packages is largely due to uneven cold airflow patterns that are caused by airflow resistance through multi-package components. The aims of this study were therefore to conduct an in-depth experimental investigation of the contribution of grape multi-packaging components to total airflow resistance, cooling rates and patterns of grapes inside the different commercially used multi-packages, and to assess the effects of these multi-packages on table grape postharvest quality attributes. A comprehensive study of moisture loss from grapes during postharvest storage and handling, as well as a preliminary investigation of the applicability of computational fluid dynamics (CFD) modeling in predicting the transport phenomena of heat and mass transfer of grapes during cooling and cold storage in multi-packages were included in this study. Total pressure drop through different table grapes packages were measured and the percentage contribution of each package component and the fruit bulk were determined. The liner films contributed significantly to total pressure drop for all the package combinations studied, ranging from 40.33±1.15% for micro-perforated liner film to 83.34±2.13 % for non-perforated liner film. The total pressure drop through the grape bulk (1.40±0.01 % to 9.41±1.23 %) was the least compared to the different packaging combinations with different levels of liner perforation. The cooling rates of grapes in the 4.5 kg multi-packaging were significantly (P<0.05) slower than that of grapes in 5 kg punnet multi-packaging, where the 4.5 kg box resulted in a seven-eighths cooling time of 30.30-46.14% and 12.69-25.00% more than that of open-top and clamshell punnet multi-packages, respectively. After 35 days in cold storage at -0.5°C, grape bunches in the 5 kg punnet box combination (open-top and clamshell) had weight loss of 2.01 – 3.12%, while the bunches in the 4.5 kg box combination had only 1.08% weight loss. During the investigation of the effect of different carton liners on the cooling rate and quality attributes of ‘Regal seedless’ table grapes in cold storage, the non-perforated liner films maintained relative humidity (RH) close to 100 %. This high humidity inside non-perforated liner films resulted in delayed loss of stem quality but significantly (P ≤ 0.05) increased the incidence of SO2 injury and berry drop during storage compared to perforated liners. The perforated liners improved fruit cooling rates but significantly (P ≤ 0.05) reduced RH. The low RH in perforated liners also resulted in an increase in stem dehydration and browning compared to non-perforated liners. The moisture loss rate from grapes packed in non-perforated liner films was significantly (P<0.05) lower compared to the moisture loss rate from grapes packed in perforated liner films (120 x 2 mm and 36 x 4 mm). The effective moisture diffusivity values for stem parts packed in non-perforated liner films were lower than the values obtained for stem parts stored without packaging liners, and varied from 5.06x10-14 to 1.05x10-13 m2s-1. The dehydration rate of stem parts was inversely proportional to the size (diameter) of the stem parts. Dehydration rate of stems exposed (without liners) to circulating cold air was significantly (P<0.05) higher than the dehydration rates of stems packed in non-perforated liner film. Empirical models were successfully applied to describe the dehydration kinetics of the different parts of the stem. The potential of cold storage humidification in reducing grape stem dehydration was investigated. Humidification delayed and reduced the rate of stem dehydration and browning; however, it increased SO2 injury incidence on table grape bunches and caused wetting of the packages. The flow phenomenon during cooling and handling of packed table grapes was also studied using a computational fluid dynamic (CFD) model and validated using experimental results. There was good agreement between measured and predicted results. The result demonstrated clearly the applicability of CFD models to determine optimum table grape packaging and cooling procedures.
AFRIKAANSE OPSOMMING: Naoes kwaliteit van vars tafeldruiwe word gewoonlik behou deur middel van verkoeling van die produk met koue lug. Ongelukkig word die effektiwiteit van dié verkoeling beïnvloed deur die multivlakverpakking wat kommersieel gebruik word vir die naoes hantering van druiwe. Daar is gewoonlik ruimtelike variasie in die temperatuur van die druiwe wat ongewenste variasie in die kwaliteit van die druiwe veroorsaak tydens naoes hantering en bemarking. Die heterogene druiwetemperature binne die multivlakverpakkings word grootliks veroorsaak deur onegalige lugvloeipatrone van die koue lug as gevolg van die weerstand wat die verskillende komponente van die multivlakverpakkings teen lugvloei bied. Die doel van hierdie studie was dus om ‘n indiepte eksperimentele ondersoek te doen om die bydrae van multivlakverpakking op totale lugvloeiweerstand, verkoelingstempo’s en –patrone van druiwe binne kommersieël gebruikte multivlakverpakkings te ondersoek, asook die effek van die multivalkverpakking op die naoes kwaliteit van druiwe te bepaal. ‘n Omvattende studie van vogverlies van druiwe tydens naoes opberging en hantering, asook ‘n voorlopige ondersoek na die bruikbaarheid van ‘n berekende vloei dinamika (BVD) model om die bewegingsfenomeen van hitte en massa oordrag van druiwe tydens verkoeling en koelopberging in multivlakverpakkings te voorspel, was ook by die studie ingesluit. Die totale drukverskil deur verskillende tafeldruif verpakkingssisteme is gemeet en die persentasie wat deur elke verpakkingskomponent en die vruglading bygedra is, is bereken. Van al die verpakkingskombinasies wat gemeet is, het die voeringfilms betekenisvol tot die totale drukverskil bygedra, en het gewissel van 40.33±1.15% vir die mikro geperforeerde voeringfilm tot 83.34±2.13 % vir die nie-geperforeerde voeringfilm. Die totale drukverskil oor die druiflading (1.40±0.01 % to 9.41±1.23 %) was die minste in vergelyking met die verskillende verpakkingskombinasies met die verskillende vlakke van voeringperforasies. Die verkoelingstempos van die druiwe in die 4.5 kg multiverpakking was betekenisvol (P<0.05) stadiger as vir die druiwe in die 5 kg handmandjie (‘punnet’) multiverpakking. Die 4.5 kg karton het ‘n seweagstes verkoelingstyd van 30.30-46.14% en 12.69-25.00% langer, respektiewelik, as oop-vertoon en toeslaan-‘punnet’ multiverpakkings gehad. Na 35 dae van koelopberging by -0.5°C het druiwetrosse in die 5 kg ‘punnet’-kartonkombinasies (oop-vertoon en toeslaan-’punnet’) ‘n massaverlies van 2.01 – 3.12% gehad, terwyl die trosse in die 4.5 kg kartonkombinasie slegs ‘n 1.08% massaverlies gehad het. In die ondersoek na die effek van verskillende kartonvoerings op die verkoelingstempo en kwaliteitseienskappe van ‘Regal seedless’ tafeldruiwe tydens koelopbering, het die nie-geperforeerde kartonvoerings ‘n relatiewe humiditeit (RH) van byna 100 % gehandhaaf. Hierdie hoë humiditeit in die nie-geperforeerde voeringfilms het ‘n verlies in stingelkwaliteit vertraag, maar het die voorkoms van SO2-skade en loskorrels betekenisvol (P < 0.05) verhoog in vergelyking met geperforeerde voerings. Die geperforeerde voerings het vrugverkoelingstempos verbeter, maar het die RH betekenisvol (P ≤ 0.05) verlaag. Die lae RH in die geperforeerde voerings het gelei tot ‘n verhoging in stingeluitdroging en –verbruining in vergelyking met die nie-geperforeerde voerings. Die vogverliestempo uit druiwe verpak in nie-geperforeerde voeringfilms was betekenisvol (P<0.05) stadiger in vergelyking met druiwe verpak in geperforeerde voeringfilms (120 x 2 mm and 36 x 4 mm). Die effektiewe vogdiffusiewaardes vir stingelgedeeltes verpak in nie-geperforeerde voeringfilms was stadiger as vir stingelgedeeltes wat verpak is sonder verpakkingsvoerings, en het gevarieer van 5.06x10-14 – 1.05x10-13 m2s-1. Die uitdrogingstempo van stingelgedeeltes was omgekeerd eweredig aan die grootte (deursnit) van die stingelgedeeltes. Die uitdrogingstempo van stingels wat blootgestel was (sonder voerings) aan sirkulerende koue lug was betekenisvol (P<0.05) hoër as die uitdrogingstempos van stingels wat verpak was in nie-geperforeerde voeringfilms. Empiriese modelle is gebruik om die uitdrogingskinetika van die verskillende stingelgedeeltes te beskryf. Die potensiaal van koelkamer humidifisering in die vermindering van die uitdroging van druifstingels is ondersoek. Humidifisering het stingeluitdroging vertraag en het die tempo van stingeluitdroging en -verbruining verminder, maar dit het die voorkoms van SO2-skade op die tafeldruiftrosse verhoog en het die verpakkings laat nat word. Die bewegingsfenomeen tydens verkoeling en hantering van verpakte tafeldruiwe is ook ondersoek deur gebruik te maak van ‘n BVD model en is bevestig met eksperimentele resultate. Daar was goeie ooreenstemming tussen gemete en voorspelde resultate. Die resultaat demonstreer duidelik die toepaslikheid van BVD-modelle om die optimum tafeldruifverpakkings- en verkoelingsprosedures te bepaal.
PPECB and Postharvest Innovation Programme (PHI-2) for their financial support
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Nidhi, R. "Studies on high carbon dioxide modified atmosphere packaging on storage quality of potatoes and selected fruits." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534185.
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Lobaton-Sulabo, April Shayne. "Packaging and storage effects on Listeria monocytogenes reduction and attachment on ready-to-eat meat snacks." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18213.
Full textAbstract:
Doctor of PhilosophyFood Science Institute
Elizabeth A. E. Boyle
A total of three studies were conducted to evaluate the effects of different packaging systems and storage times on reduction of Listeria monocytogenes on ready-to-eat meat snacks. Study 1 was conducted to determine the effects of four packaging systems [heat sealed (HS), heat sealed with oxygen scavenger (HSOS), nitrogen flushed with oxygen scavenger (NFOS), and vacuum (VAC)] and storage times (24, 48, and 72 h, and 14 and 30 d) on reduction of L. monocytogenes in turkey jerky in the presence or absence of sodium nitrite. Inclusion of sodium nitrite in turkey jerky did not affect (P>0.05) L. monocytogenes log reductions regardless of packaging type or storage time. After 14 d of storage in HSOS, NFOS, or VAC, and 48 or 72 h in HS, a reduction of >1.0 log CFU/cm² of L. monocytogenes was achieved. Processors could use HS in conjunction with 48 h of ambient storage and be in compliance with the United States Department of Agriculture Food Safety and Inspection Service Listeria Rule of post-lethality treatment in achieving at least 1 log reduction of L. monocytogenes. Study 2 was conducted to investigate attachment of L. monocytogenes to uncured and cured turkey jerky packaged in HS, HSOS, NFOS, or VAC using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The SEM examination showed that L. monocytogenes is capable of adhering to uncured or cured turkey jerky surfaces. Elemental maps from EDS analysis revealed that no element was unique or elevated at sites of L. monocytogenes attachment. Elemental composition showed the presence of elemental sulfur and could be an indication of the presence of sulfur-containing amino acids in turkey jerky. Finally, Study 3 evaluated the affects of two packaging types (HSOS and NFOS) and four ambient storage times (24, 48, and 72 h, and 14 d) on reduction of L. monocytogenes on five commercial RTE meats and poultry snacks (beef tenders, beef jerky, beef sausage sticks, pork jerky, and turkey sausage sticks). A mean reduction of >1.0 log CFU/cm² of L. monocytogenes was achieved on all products, regardless of packaging or storage time. Correlation analysis provided some indication that reduction of L. monocytogenes increased with fat content. However, the strength of linear correlation was not sufficient to account for the differences in log reduction in L. monocytogenes. In study 1, a holding time of 24, 48, or 72 h for HSOS or NFOS packaging of was not effective for reducing L. monocytogenes by at least 1 log on turkey jerky. In contrast, packaging beef tenders, beef jerky, beef sausage sticks, pork jerky, and turkey sausage sticks in HSOS or NFOS for at least 24 h ambient storage was sufficient to achieve at least 1 log reduction in L. monocytogenes population. Specific components such as sulfur-containing amino acids in turkey jerky might be contributing to <1 log reduction of L. monocytogenes population on turkey jerky after 24, 48, or 72 h of ambient storage. Overall, nitrite was not an effective ingredient to control L. monocytogenes in turkey jerky. However, packaging such as HS, HSOS, NFOS or VAC and at least 24 h holding time were effective hurdles for controlling L. monocytogenes at post-lethality.
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Uppal, Kamaldeep Kaur. "Effect of packaging and storage time on survival of Listeria monocytogenes on shelf-stable meat snacks." Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/7054.
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Master of ScienceFood Science Institute
Kelly J. K. Getty
The United States Department of Agriculture’s Food Safety and Inspection Service require that processors of ready-to-eat (RTE) meat and poultry products implement post- processing intervention strategies for controlling Listeria monocytogenes. The objective of our study was to determine the effect of packaging methods and storage time on reducing L. monocytogenes in shelf-stable meat snacks. Commercially available kippered beef steak strips (14 × 2.5 cm rectangle piece) and turkey tenders (4 × 4 cm square piece) were dipped into a five-strain L. monocytogenes cocktail, and dried at 23°C until a water activity of approximately 0.80 was achieved. Inoculated samples were packaged with four treatments: 1) vacuum, 2) nitrogen flushed with oxygen scavenger, 3) heat sealed with oxygen scavenger, and 4) heat sealed without oxygen scavenger. Samples were stored at 23°C and evaluated for L. monocytogenes levels at 0, 24, 48, and 72 h. Initial levels (time 0) of L. monocytogenes were approximately 5.7 log CFU/cm[superscript]2 for steak and tenders. For kippered beef steak, there was no interaction among packaging treatments and storage times (P > 0.05) whereas, storage time was different (P <0.05). A 1 log reduction of L. monocytogenes was observed at 24 and 48 h at 23°C for all packaging treatments and a 2.1 log CFU/cm[superscript]2 reduction occurred at 72 h. A 1 log CFU/cm[superscript]2 reduction of L. monocytogenes was observed after 24 h of storage for turkey tenders for all packaging treatments. After 48 h of storage time turkey tenders showed >1 log CFU/cm [superscript]2 reduction of L. monocytogenes for all packaging treatments except for vacuum packaged where only 0.9 log CFU/cm[superscript]2 reduction was observed. Log reductions at 72 h for all packaging treatments for turkey tenders ranged from 1.5 to 2.2. Processors of kippered beef steak and turkey tenders could use vacuum, nitrogen-flushing, or heat sealed with an oxygen scavenger packaging methods and hold product 24 h prior to shipping to reduce potential L. monocytogenes numbers by ≥1 log. However, processors should be encouraged to hold packaged product a minimum of 72 h to enhance the margin of safety for L. monocytogenes control.
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Yoo, Jiyoun. "Quantitative Analysis of the Compressive Stress Distributions across Pallet Decks Supporting Packaging in Simulated Warehouse Storage." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/35737.
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The primary objective of this study was to quantitatively analyze compressive static stress distributions across pallet deck surfaces supporting flexible and rigid packaging in simulated warehouse storage systems. Three different densities of polyolefin foams (2, 4, and 6 lb/ft3, pcf) simulated a variety of flexible and rigid packaging with a range of stiffness properties. A layer of single wall C-flute corrugated fiberboard acted as a sensing medium and also simulated the bottom of a corrugated box. Pressure sensitive films were used to detect compressive static stresses at the interface between the polyolefin foams and the pallet deckboard. Image analysis computer software program was developed to quantitatively characterize stress distributions left on pressure sensitive film. 280 lbs of compression load were applied to a Plexiglas® pallet section (40 x 3.5 inches, L x W) with ¾ inch deck thickness, as well as to a steel pallet section (40 x 3.5 inches, L x W) with ½ inch deck thickness. In both cases, the pallet sections were used in a simulated pallet storage rack. 700 lbs of compression load were applied to the same steel pallet section that was used in the racking simulation and the Plexiglas® pallet sections (40 x 3.5 inches, L x W) with ½ and ¾ inch deck thicknesses were used in simulated block (floor) stack storage to measure the stress distributions and deflections of deckboards. Applying the final models of resultant non-uniform stress distributions enabled the development of finite element analysis (FEA) models of pallet deckboard deflections. The predicted FEA models of the deckboard deflections were validated through comparison with experimentally measured deflections in the simulated warehouse storage systems.
In the final models, the resultant three foamsâ stress distributions across pallet deck surfaces in both rack and floor stack storage simulations were non-uniform. The changes in the degree of stress concentrations and maximum stress levels along the deckboards varied, depending on the stiffness of the foams and deckboards and the support conditions in the simulated warehouse storage models. Qualified test indicates that the 2pcf and 4pcf foams represent non-rigid sack products and the 6pcf foam represents rigid packaging and contents. All tests were conducted within a few minutes; hence, all test data were assumed to be initially resulted compressive stresses. The compressive stresses may change over time. The measure of stress concentrations is the stress intensity factor, which is the ratio of initial maximum resultant compressive stress to the applied stress. The initial maximum resultant compressive stresses were adjusted for rate of loading which varied due to the difference in the stiffness of the foams. The table below shows the adjusted initial maximum resultant compressive stress intensity factors. The product of the calculation uniformly distributed compressive stress and the stress intensity factor is the appropriate criteria for designing packaging of product with adequate compressive strength. These factors will be useful when designing pallets, packaging, and unit loads.In simulated block stack storage, the foam stiffness (package and product stiffness) had a more significant effect on the stress distributions and concentrations along the deckboards than did the pallet deck stiffness. As a result, the stiffer foam presented a greater change in stress levels along the deckboard under the compression load. The quantified and evaluated stress concentrations and stress distributions will be useful in understanding the interactions between pallets and packaging, reducing product damage and improving the safety of the work place during the long-term storage of the unit loads. The predicted FEA models will allow the industry to better optimize pallets, packaging, and unit load designs.Master of Science
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Caminiti, Jeff Thomas Caminiti. "Influence of Storage Temperature on Changes in Frozen Meat Quality." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1532021659638583.
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Ayvaz, Huseyin. "Influence of Packaging Material and Storage Conditions on the Quality Attributes of Pressure-Assisted Thermally Processed Carrots." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281125846.
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SILVA, TERESINHA de M. da. "Contribuição ao transporte de materiais físseis na armazenagem em trânsito." reponame:Repositório Institucional do IPEN, 2005. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11349.
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Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Ganeco, Aline Giampietro [UNESP]. "Qualidade de ovos embalados com atmosfera modificada e armazenados em temperatura ambiente." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/96509.
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ganeco_ag_me_jabo.pdf: 403489 bytes, checksum: 6c0643f4ad7f4d805acb473ab867a830 (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O estudo avaliou as características físicas, químicas e microbiológicas de ovos armazenados com atmosfera modificada em temperatura ambiente. Foram utilizados 1224 ovos comerciais e embalados em estojos de plástico de doze ovos, envoltos em sacos plásticos. Os ovos acondicionados à vácuo, à vácuo com sequestradores de gás oxigênio, à vácuo com sequestradores de gás oxigênio e sequestradores de gás carbônico e à vácuo com sequestradores de gás oxigênio e gerador de gás carbônico, submetidos a 7, 14, 21 e 28 dias de armazenamento, sob temperatura ambiente. Foi utilizado um delineamento inteiramente casualizado em esquema fatorial 4x4+1 com 3 repetições de 4 ovos cada. As características avaliadas foram: manutenção de peso durante armazenamento, unidade Haugh, índice gema, coloração da gema, atividade de água, pH da gema e do albúmen e o teste de Substâncias Reativas ao Ácido Tiobarbitúrico (TBARs). As embalagens com atmosfera modificada mantiveram os pesos dos ovos por um período de 28 dias e a com vácuo com sequestrante de O2 e geradores de CO2, foi a que apresentou melhores valores para a unidade Haugh e para o índice gema. Conclui-se que o vácuo provocou efeito positivo na qualidade interna dos ovos, e estes, quando armazenados em estojos que continham sequestrador de gás oxigênio (O2) e gerador de gás carbônico (CO2) preservaram ainda mais suas características internas. Foram quantificados também bolores e leveduras, cujos resultados foram transformados em número de UFC por ovo para Log 10. As embalagens que continham saches sequestrantes de gás oxigênio e as com saches sequestrantes de gás oxigênio e gás carbônico, mantiveram as características de ovos frescos na população de bolores e leveduras até aos sete dias de armazenamento em temperatura ambiente
The study evaluated the physical, chemical and microbiological characteristics of eggs stored at different vacuum conditions and ambient temperature. Were used 1224 commercial laying hens eggs and were packed in plastic cases of twelve eggs and each envolved in plastic bags (types of vacuum packaging: case; hijacker case with oxygen gas (O2); hijacker case with oxygen gas (O2) and carbon dioxide (CO2); case with hijacker oxygen gas (O2) and generates carbon dioxide (CO2)) and subjected to 7, 14, 21 and 28 days of storage at room temperature. Were used a completely randomized factorial 4x4 +1 (types of packaging and storage periods + control - fresh eggs), with three repetitions of four eggs each. These characteristics were: maintenance of weight during storage, Haugh unit, yolk index, yolk color, water activity, pH of yolk and albumen and testing of Thiobarbituric Acid Reactive Substances. The atmosphere modified packaging keeps the weights of the eggs for a period of 28 days and the vacuum scavenger of O2 and CO2 generators, showed the best values for Haugh unit and yolk index. Analysis and quantification of molds and yeasts, whose results were transferred in the number of CFU per egg molds, yeasts and Log 10. Concluded that the vacuum caused positive effect on internal egg quality, and these, when stored in kits containing kidnapper of oxygen gas (O2) and generates carbon dioxide (CO2) preserved even its internal characteristics. The packaging sachets containing sequestrants with oxygen gas and oxygen gas sachets and sequestering carbon dioxide, provided eggs with characteristic patterns of fresh eggs to seven days of storage at room temperature
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Brito, Selma Freire de. "Biometrics, morphology, seeds and storage of initial growyh Acnistus arborescens (L.) Schltdl." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7351.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoMarianeira is a medicinal specie whose active principle has anti-tumor activity. This research has as objective realize the biometric and morphologic characterization of fruits, seeds and seedlings, germination, storage and initial growth in different shading levels. The biometry was evaluated in a sample of 50 fruits and 100 seeds. Firstly, the germination morphology was done in BOD and the development post-seminal was evaluated in greenhouse. In the study about the germination, it was evaluated the combination of temperature (20, 25, 30 and 20-30 ÂC) and the addition of KNO3 in the substrate (without and with 0,2% of KNO3), in a completely randomized design with four replicates, and was analyzed the percentage, speed index and mean time of germination. The factors involved in the storage experiment were environment (environment, refrigerator and cold chamber), package (glass, plastic bag and aluminized paper) and period of storage (3, 6 and 9 months) disposed in split-plot according to a completely randomized design. The initial growth was evaluated under the combination of four shading conditions (0, 50, 70 and 90% of shading) and five plants age (30, 51, 72, 93 and 114 days after the transplant), disposed in a split-plot scheme according to a randomized block design with four replicates, and were analyzed the height, diameter, root length, leaf number, dry weight of leaves, stem, root and total, besides of the chlorophyll relative index, leaf area, leaf area ratio, specific leaf area and specific leaf weight. The fruit is indehiscent, fleshy, globular and polyspermic, it weighs 0,53 g and has 46 seeds. The seeds have ellipsoidal shape and the embryo is curve and the endosperm is white. The seeds present the following measures: 1.59 mm of length, 1.33 mm of width and 0.36 mm of thickness. The germination is phanero-epigeal with leaf cotyledons. The temperatures recommended to evaluate the germination were 20 ÂC and 20-30 ÂC with KNO3 (0,2%), presenting 75 and 71% of germination. Cold room and refrigerator were the most suitable environments for the preservation of seeds for nine months when stored in glass and plastic. Under natural conditions the glass container is ideal for storage for 3 months. The shade favored early growth marianeira
Marianeira à uma espÃcie medicinal cujo princÃpio ativo possui atividade antitumoral. Objetivou-se nesta pesquisa realizar a caracterizaÃÃo biomÃtrica e morfolÃgica de frutos, sementes e plÃntulas, germinaÃÃo, armazenamento e crescimento inicial em diferentes nÃveis de sombreamento. A biometria foi avaliada em uma amostra de 50 frutos e 100 sementes. A morfologia da germinaÃÃo foi feita inicialmente em cÃmara de germinaÃÃo e o desenvolvimento pÃs-seminal em casa de vegetaÃÃo. No estudo da germinaÃÃo avaliou-se a combinaÃÃo de temperatura (20, 25, 30 e 20-30ÂC) e aplicaÃÃo de KNO3 no substrato (sem e com 0,2% de KNO3), no delineamento inteiramente casualizado com quatro repetiÃÃes, sobre a porcentagem, velocidade e tempo mÃdio de germinaÃÃo. Os fatores envolvidos no experimento de armazenamento foram ambiente (natural, geladeira e cÃmara fria), embalagem (vidro; saco plÃstico e papel aluminizado) e perÃodo de estocagem (3; 6 e 9 meses) dispostos num esquema de parcelas subsubdivididas num delineamento inteiramente casualizado com quatro repetiÃÃes. No crescimento inicial testaram-se quatro condiÃÃes de sombreamento (0, 50, 70 e 90% de sombreamento) e cinco idades da planta (30, 51, 72, 93 e 114 dias apÃs a repicagem), dispostos em parcelas subdivididas no delineamento de blocos ao acaso com quatro repetiÃÃes, sobre a altura, diÃmetro, comprimento da raiz, nÃmero de folhas, peso da matÃria seca das folhas, caule, raiz e total e Ãndice relativo de clorofila, Ãrea foliar, razÃo de Ãrea foliar, Ãrea foliar especÃfica e peso especÃfico da folha. O fruto à indeiscente, carnoso, globoso e polispÃrmico, pesa 0,53 g e contem 46 sementes. As sementes sÃo de formato elipsoidal sendo o embriÃo curvo e o endosperma esbranquiÃado. As sementes apresenta as seguintes medidas: 1,59 mm de comprimento, 1,33 mm de largura e 0,36 mm de espessura. A germinaÃÃo à do tipo fanerocotiledonar, epÃgea, com cotilÃdones foliÃceos. As temperaturas recomendadas para avaliaÃÃo da germinaÃÃo foram 20 e 20- 30ÂC na presenÃa de KNO3 a 0,2%, com 75 e 71% de germinaÃÃo, respectivamente. CÃmara fria e geladeira foram os ambientes mais adequados à conservaÃÃo das sementes por nove meses, quando acondicionadas em vidro e saco plÃstico. Em ambiente natural o recipiente de vidro à ideal para o armazenamento, durante 3 meses. O sombreamento favoreceu o crescimento inicial de marianeira
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Ho, Son Hong. "Numerical modeling and simulation for analysis of convective heat and mass transfer in cryogenic liquid storage and HVAC&R applications." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002266.
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Berry, Tarl Michael. "Resistance to airflow and the effects on cooling efficiency of multi-scale ventilated pome fruit packaging." Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85685.
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Thesis (MScAgric)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Inadequate cooling of produce after it has been packed into ventilated packaging can result in inconsistent fruit quality. Misalignment of ventilation holes during stacking as well as the use of internal packaging, such as trays, polyliner bags and thrift bags reduces airflow distribution through the packaging. Consequently, the complex needs of maintaining the cold chain of perishable produce and the considerable variations in packaging designs have made it challenging to find an optimal ventilated package and stacking arrangement. The aims of this study were, therefore, to assess the status of ventilated packaging in the South African pome fruit industry, and to characterize the effects of package design and multi-scale packaging components on the resistance to airflow and cooling performance of apples under forced-air cooling conditions. A survey of the pome fruit industry identified over twenty packaging designs which were grouped into eleven unique designs and further categorised into either ‘display’ or ‘telescopic’ designs. Although South African fruit industry standards recommend ventilation areas of at least 5%, the ventilation areas of package designs identified from the survey varied considerably between <1 and 11%. Furthermore, the study showed that use of stacking renders many of the ventilation holes ineffective, due to blockages from adjacent cartons. The contribution of each component of the multi-scale packages used for handling apples was determined by analysis of pressure drop during forced-air cooling. The results showed when utilising a combination of cartons, fruit trays and plastic liner bags, the total pressure drop contribution of the cartons (8%) and fruit trays (3%) was minimal, while the use of plastic liner bags contributed 89%. However, in a carton and thrift bag packaging combination, the thrift bags contributed 66% to the pressure drop while the carton contributed 34%. The cooling results indicated a negative correlation between the total stack ventilation area and the cooling heterogeneity. In addition, the airflow velocity was correlated positively with fruit cooling rate and negatively with total moisture loss. Fruit packed inside polyliner bags had cooling rates four times slower than fruit on trays and three times slower in thrift bags. The use of liner bags blocked the ventilation holes, thereby reducing the airflow velocity. As a result of the longer cooling times in the polyliner bags, fruit remained at higher temperatures for longer periods, resulting in up to three times more moisture loss during forced-air cooling. In addition, a temperature gradient formed due to a progressive increase in air temperature through the stack, thereby resulting in a similar gradient of moisture loss. This research showed that airflow velocity and distribution were the most important factors contributing to the effectiveness of fruit cooling in multi-scale packaging. From a cold chain perspective, future packaging designs should therefore focus on optimising ventilation characteristics and alignment during stacking to ensure adequate airflow. Given the contribution of internal packaging to high resistance to airflow, such packaging components should be used with caution and only when necessary to meet physiological and market requirements.
AFRIKAANSE OPSOMMING: Onvoldoende verkoeling van vars produkte nadat hulle verpak is kan lei tot wisselende vruggehalte. Wanbelyning van ventilasiegate tydens stapeling sowel as die gebruik van interne verpakking soos rakkies (eng. “trays”), poli-etileensakke en drasakkies (eng. “thrift bag”) verminder die lugverspreiding deur die verpakking. Komplekse behoeftes om bederfbare produkte in die koue ketting te behou en die aansienlike verskille in verpakkingsontwerpe het dit 'n uitdaging gemaak om 'n optimale geventileerde verpakking en stapelskikking of -rangskikking te vind. Die doelwitte van hierdie studie was dus om die status van geventileerde verpakking in die Suid-Afrikaanse kernvrugbedryf te asseseer, en die gevolge van die verpakkingsontwerp en multi-skaal verpakkingskomponente op die weerstand teen lugvloei en verkoeling van appels onder geforseerde lugverkoeling te bepaal. ‘n Opname van die kernvrugbedryf het meer as twintig verpakkingsontwerpe geïdentifiseer, wat in elf unieke ontwerpe gegroepeer is en verder getipeer word in ‘vertoon’ en ‘teleskopiese’ kartonontwerpe. Alhoewel die Suid-Afrikaanse vrugindustrie-standaarde ventilasie areas van ten minste 5% aanbeveel, het die ventilasie areas van die verpakkingsontwerpe geïdentifiseer uit die opname aansienlik gewissel tussen <1 en 11%. Verder het die studie getoon dat gebruik van stapeling baie van die ventilasiegate ondoeltreffend laat weens blokkasies veroorsaak deur aangrensende kartonne. Die bydrae van elke komponent van die multi-skaal verpakkingskombinasies gebruik vir die hantering van appels was bepaal deur analise van die afname in lugdruk tydens geforseerde lugverkoelingskondisies. Die resultate het getoon dat wanneer ‘n kombinasie van kartonne, polietileensakke en vrugte plus rakkies gebruik word, die bydrae van die kartonne (8%) en vrugte plus rakkies (3%) tot die totale afname in lugdruk minimaal was, terwyl die gebruik van polietileensakke ‘n 89% bydrae gemaak het. In ‘n karton en drasakkie kombinasie het die drasakkies 66% bygedra tot die afname in lugdruk, terwyl die karton 34% bygedra het. Die verkoelingsresultate het 'n negatiewe korrelasie getoon tussen die totale stapelventilasie-area en die verkoelingsheterogeniteit. Daarbenewens was die lugvloeisnelheid positief gekorreleer met vrugverkoelingstempo en negatief gekorreleer met totale vogverlies. Die verkoelingstydperk van vrugte in die poli-etileensakke was vier keer langer as die rakkie met vrugte kombinasie en drie keer langer in die drasakkies. Die poli-etileensakke het die ventilasiegate versper en dus die lugvloeisnelheid verlaag. Weens die langer verkoelingstye in die poli-etileensakke was vrugte veel langer aan hoër temperature blootgestel, wat uiteindelik gelei het tot drie keer meer massaverlies gedurende geforseerde lugverkoeling. Daarby het ‘n temperatuurgradiënt gevorm as gevolg van ‘n progressiewe verhoging in lugtemperatuur deur die stapel wat gelei het tot ‘n gelykstaande gradiënt van vogverlies. Hierdie navorsing het getoon dat die lugvloeisnelheid en -verspreiding die belangrikste faktore was wat die doeltreffendheid van vrugverkoeling in multi-skaal verpakking geaffekteer het. Uit 'n koelketting perspektief moet die toekomstige verpakkingsontwerpe dus fokus op die optimalisering van ventilasie eienskappe en belyning (eng. “alignment”) tydens stapeling om voldoende lugvloei te verseker. Gegewe die bydrae van die interne verpakking tot hoë weerstand teen lugvloei, moet sulke verpakkingskomponente met omsigtigheid gebruik word en slegs wanneer dit nodig is om aan markvereistes te voldoen.
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Paula, Jose Aluisio de Araujo. "Produção e qualidade em frutos de bananeira propagados por diferentes tipos de mudas." Universidade Federal Rural do Semi-Árido, 2016. http://bdtd.ufersa.edu.br:80/tede/handle/tede/592.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The culture of banana plantation, besides presenting a differential with respect to the intake of agricultural inputs, being little demanding on their use, is a culture of production cycle quite short, where it is possible to achieve crops with economic return in the first year. The aim of this research was to evaluate the growth, productivity and quality of different banana cultivars in response to the use of different types of plants. We accomplished an experiment on the farm Terra Santa, Quixeré/CE, in order to evaluate the behavior of banana plantation cultivars propagated through conventional system. Köppen classification for the climate of the two regions is BSwh’, hot and dry. With basis on the results obtained, we assembled three essays, the first one was in factorial scheme 2 x 3, with four blocks and six repetitions in each block to study the growth and development of the two banana cultivars propagated by rhizome and meristems and cultivated with conventional management; the second one was a DIC in factorial scheme 6 x 3, with eight repetitions, in order to assess the behavior of the treatments tested for cultivars when submitted to 20 days stored under refrigeration and the third one was a DIC in factorial scheme 6 x 3, with two repetitions, in order to evaluate the behavior of the treatments tested for cultivars when submitted to fifteen days stored under refrigeration and five days of packaging in ambient temperature. The results showed the number of alive leaves per plant of cultivar Prata-anã surpassed Pacovan cultivar and there was not significant effects between cultivars for the features of flowering range and number of alive blooms in the flowering period. The effect of the range from planting to the crop is highly associated to the effect of the range from the flowering to crop. The cultivar Prata-anã overcame the cultivar Pacovan in the number of bunches per cluster and in the number of fruit per bunch. The cultivar Pacovan overcame the Prata-anã on the effects of length, diameter and fruit weight from the essay. The storage of banana fruit under refrigeration was efficient on delaying the process of post-harvest fruit maturation. The cultivar Prata-anã propagated by rhizome with “bait” was the most efficient propagation technique, among all tested, on the obtaining of soluble solids and acidity level, but obtained the lowest pH rate. The post-harvest fruit packaging under ambient temperature strengthened the acquisition of vitamin C in fruit of banana “Prata-anã” propagated by meristem and dissipated banana fruit “Pacovan” propagated by rhizome without “bait”
O cultivo da bananeira além de apresentar um diferencial no que se refere ao aporte de insumos agrícolas, sendo pouco exigente ao uso destes, é uma cultura de ciclo produtivo relativamente curto, onde se consegue colheitas de retorno econômico já no primeiro ano de condução da cultura. O objetivo da presente pesquisa foi avaliar o crescimento, a produção e a qualidade de diferentes cultivares de bananeira em resposta ao uso de diferentes tipos de mudas. Foi realizado um experimento na Fazenda Terra Santa, Quixeré/CE, para avaliar o comportamento de cultivares de bananeira propagadas pelo sistema convencional. A classificação de Köppen para o clima das duas regiões é do tipo BSwh’, caracterizado como quente e seco. Com base nos resultados obtidos foram montados três ensaios sendo o primeiro, um DBC em esquema fatorial 2 x 3, com 04 blocos e 06 repetições em cada bloco para estudar o crescimento e o desenvolvimento das duas cultivares de bananeira propagadas por rizoma e meristemas e cultivadas no manejo convencional, o segundo um DIC em esquema fatorial 6 x 3, com 08 repetições, para avaliar o comportamento dos tratamentos testados para cultivares quando submetidos a 20 dias de armazenados sob refrigeração e o terceiro um DIC em esquema fatorial 6 x 3, com 02 repetições, para avaliar o comportamento dos tratamentos testados para cultivares quando submetidos a 15 dias de armazenados sob refrigeração e 5 dias de acondicionamento em temperatura ambiente. Os resultados evidenciaram que o número de folhas vivas por planta da cultivar Prata-anã superou a cultivar Pacovan e não houve efeitos significativos entre as cultivares para as características do ensaio de intervalo de floração e número de brotações vivas no período da floração. O efeito de intervalo do plantio a colheita esta fortemente associado ao efeito do intervalo da floração a colheita. A cultivar Prata-anã superou a cultivar Pacovan no número de pencas por cacho e no número de frutos por penca. A cultivar Pacovan superou a cultivar Prata-anã nos efeitos de comprimento, diâmetro e peso de frutos do ensaio.. O armazenamento de frutos de bananeira sob refrigeração foi eficiente no retardamento do processo de maturação pós-colheita da fruta. A cultivar Prata-anã propagada por rizoma com “ceva” foi a mais eficiente forma de propagação, dentre as testadas, na obtenção de sólidos solúveis e teor de acidez, porém foi a que obteve os menores índices de pH. O acondicionamento pós-colheita de frutos a temperatura ambiente funcionou como potencializador na aquisição de vitamina C em frutos de bananeira ‘Prata-anã’ propagada por meristema e como dissipador em frutos de bananeira ‘Pacovan’ propagada por rizoma sem “ceva”
2017-01-10
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Molina, Montoya Eduardo. "Modeling of the fundamental mechanical interactions of unit load components during warehouse racking storage." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/102266.
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The global supply chain has been built on the material handling capabilities provided by the use of pallets and corrugated boxes. Current pallet design methodologies frequently underestimate the load carrying capacity of pallets by assuming they will only carry uniformly distributed, flexible payloads. But, by considering the effect of various payload characteristics and their interactions during the pallet design process, the structure of pallets can be optimized. This, in turn, will reduce the material consumption required to support the pallet industry.
In order to understand the mechanical interactions between stacked boxes and pallet decks, and how these interactions affect the bending moment of pallets, a finite element model was developed and validated. The model developed was two-dimensional, nonlinear and implicitly dynamic. It allowed for evaluations of the effects of different payload configurations on the pallet bending response. The model accurately predicted the deflection of the pallet segment and the movement of the packages for each scenario simulated.
The second phase of the study characterized the effects, significant factors, and interactions influencing load bridging on unit loads. It provided a clear understanding of the load bridging effect and how it can be successfully included during the unit load design process. It was concluded that pallet yield strength could be increased by over 60% when accounting for the load bridging effect. To provide a more efficient and cost-effective solution, a surrogate model was developed using a Gaussian Process regression. A detailed analysis of the payloads' effects on pallet deflection was conducted. Four factors were identified as generating significant influence: the number of columns in the unit load, the height of the payload, the friction coefficient of the payload's contact with the pallet deck, and the contact friction between the packages. Additionally, it was identified that complex interactions exist between these significant factors, so they must always be considered.Doctor of Philosophy
Pallets are a key element of an efficient global supply chain. Most products that are transported are commonly packaged in corrugated boxes and handled by stacking these boxes on pallets. Currently, pallet design methods do not take into consideration the product that is being carried, instead using generic flexible loads for the determination of the pallet's load carrying capacity. In practice, most pallets carry discrete loads, such as corrugated boxes. It has been proven that a pallet, when carrying certain types of packages, can have increased performance compared to the design's estimated load carrying capacity. This is caused by the load redistribution across the pallet deck through an effect known as load bridging. Being able to incorporate the load bridging effect on pallet performance during the design process can allow for the optimization of pallets for specific uses and the reduction in costs and in material consumption. Historically, this effect has been evaluated through physical testing, but that is a slow and cumbersome process that does not allow control of all of the variables for the development of a general model. This research study developed a computer simulation model of a simplified unit load to demonstrate and replicate the load bridging effect. Additionally, a surrogate model was developed in order to conduct a detailed analysis of the main factors and their interactions. These models provide pallet designers an efficient method to use to identify opportunities to modify the unit load's characteristics and improve pallet performance for specific conditions of use.
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Ellis, William Otoo. "Effect of modified atmosphere packaging on the growth and aflatoxin production by Aspergillus flavus and Aspergillus parasiticus under tropical environmental storage conditions." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41118.
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The combined effect of Modified Atmosphere Packaging (MAP) involving gas packaging, oxygen absorbent and other environmental factors to control aflatoxin production by Aspergillus flavus and Aspergillus parasiticus in both synthetic media and peanuts were studied using a process optimization technique termed Response Surface Methodology (RSM). Regression analysis of the data indicated that water activity (a$ sb{ rm w}$), pH, storage temperature, initial concentration of headspace oxygen and inoculum level were all highly significant factors (p 0%). These changes in the barrier characteristics influenced the headspace gas composition within the product and under modified atmospheres hence the level of aflatoxin detected in these stored products.In conclusion, this study has shown that the combined effect of several "barriers" can be used in conjunction with low oxygen modified atmosphere and high barrier packaging films to inhibit or reduce aflatoxin to safe and acceptable levels, particularly at abusive temperatures encountered during storage.
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Ganeco, Aline Giampietro. "Qualidade de ovos embalados com atmosfera modificada e armazenados em temperatura ambiente /." Jaboticabal : [s.n.], 2012. http://hdl.handle.net/11449/96509.
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Orientador: Hirasilva BorbaBanca: Maria Regina Barbieri de Carvalho
Banca: Marcel Manente Boiago
Resumo: O estudo avaliou as características físicas, químicas e microbiológicas de ovos armazenados com atmosfera modificada em temperatura ambiente. Foram utilizados 1224 ovos comerciais e embalados em estojos de plástico de doze ovos, envoltos em sacos plásticos. Os ovos acondicionados à vácuo, à vácuo com sequestradores de gás oxigênio, à vácuo com sequestradores de gás oxigênio e sequestradores de gás carbônico e à vácuo com sequestradores de gás oxigênio e gerador de gás carbônico, submetidos a 7, 14, 21 e 28 dias de armazenamento, sob temperatura ambiente. Foi utilizado um delineamento inteiramente casualizado em esquema fatorial 4x4+1 com 3 repetições de 4 ovos cada. As características avaliadas foram: manutenção de peso durante armazenamento, unidade Haugh, índice gema, coloração da gema, atividade de água, pH da gema e do albúmen e o teste de Substâncias Reativas ao Ácido Tiobarbitúrico (TBARs). As embalagens com atmosfera modificada mantiveram os pesos dos ovos por um período de 28 dias e a com vácuo com sequestrante de O2 e geradores de CO2, foi a que apresentou melhores valores para a unidade Haugh e para o índice gema. Conclui-se que o vácuo provocou efeito positivo na qualidade interna dos ovos, e estes, quando armazenados em estojos que continham sequestrador de gás oxigênio (O2) e gerador de gás carbônico (CO2) preservaram ainda mais suas características internas. Foram quantificados também bolores e leveduras, cujos resultados foram transformados em número de UFC por ovo para Log 10. As embalagens que continham saches sequestrantes de gás oxigênio e as com saches sequestrantes de gás oxigênio e gás carbônico, mantiveram as características de ovos frescos na população de bolores e leveduras até aos sete dias de armazenamento em temperatura ambiente
Abstract: The study evaluated the physical, chemical and microbiological characteristics of eggs stored at different vacuum conditions and ambient temperature. Were used 1224 commercial laying hens eggs and were packed in plastic cases of twelve eggs and each envolved in plastic bags (types of vacuum packaging: case; hijacker case with oxygen gas (O2); hijacker case with oxygen gas (O2) and carbon dioxide (CO2); case with hijacker oxygen gas (O2) and generates carbon dioxide (CO2)) and subjected to 7, 14, 21 and 28 days of storage at room temperature. Were used a completely randomized factorial 4x4 +1 (types of packaging and storage periods + control - fresh eggs), with three repetitions of four eggs each. These characteristics were: maintenance of weight during storage, Haugh unit, yolk index, yolk color, water activity, pH of yolk and albumen and testing of Thiobarbituric Acid Reactive Substances. The atmosphere modified packaging keeps the weights of the eggs for a period of 28 days and the vacuum scavenger of O2 and CO2 generators, showed the best values for Haugh unit and yolk index. Analysis and quantification of molds and yeasts, whose results were transferred in the number of CFU per egg molds, yeasts and Log 10. Concluded that the vacuum caused positive effect on internal egg quality, and these, when stored in kits containing kidnapper of oxygen gas (O2) and generates carbon dioxide (CO2) preserved even its internal characteristics. The packaging sachets containing sequestrants with oxygen gas and oxygen gas sachets and sequestering carbon dioxide, provided eggs with characteristic patterns of fresh eggs to seven days of storage at room temperature
Mestre
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Hussein, Zaharan. "Perforation-mediated modified atmosphere packaging (PM-MAP) and shelf-life of pomegranate fruit arils (cv. ACCO)." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/96079.
Full textAbstract:
Thesis (MScFoodSc)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Perforation-mediated modified atmosphere packaging (PM-MAP) offers the possibility of optimising polymeric films in order to compensate for barrier limitations of conventional modified atmosphere packaging (MAP). The aim of this study was to investigate the effects of PM-MAP and storage duration on the physico-chemical quality attributes, microbial quality, phytochemicals (anthocyanins, phenolics and ascorbic acid) and antioxidant activities of arils from fresh minimally processed pomegranate (cv. Acco). The effects of number of perforations (0, 3, 6 and 9; Ø = 0.8 mm) and storage temperature (5, 10 and 15 ºC) on water vapour transmission rate (WVTR, g/m2.day) of synthetic ‘Polylid’ and biodegradable (Nature flexTM) polymeric films were investigated. The results showed that non-perforated biodegradable film had higher WVTR at all storage temperatures, and irrespective of film type, increasing the number of perforations (from P-3 to P-9) had higher impact on WVTR than increasing storage temperature (from 5 to 15 ºC). Furthermore, this study investigated the effects of PM-MAP on the physico-chemical properties, phytochemicals components and antioxidant activities of fresh minimally processed arils. Arils (100 g) were packaged in polypropylene trays (10.6 x 15.1 cm2) and heat-sealed with a polymeric film POLYLID®. Perforations (0, 3, 6 and 9; Ø = 0.8 mm) were made on the top of the film and all samples were stored at 5 ± 1 ºC and 95 ± 2% relative humidity for 14 days. Samples were analysed at intervals of 3, 6, 9, 12 and 15 days. Microbial analysis included tests for Escherichia coli, aerobic mesophilic bacteria, yeast and moulds at days 0, 6, 10 and 14. The results showed that headspace gas composition was significantly influenced by the number of perforations, which helped balance the decrease in O2 with corresponding increase in CO2 levels, thus preventing anoxic conditions. Total soluble solids, titratable acidity and firmness of arils were slightly reduced by PM-MAP compared to clamshell trays. Colour attributes was generally maintained across all treatments and throughout the storage duration. The highest counts of aerobic mesophilic bacteria (5.5 log CFU/g), yeast and moulds (5.3 log CFU/g) were observed in P-0 and P-9 packages, respectively. Overall, P-3 and P-6 better maintained the physico-chemical properties and microbial quality of arils. Total phenolics and anthocyanin contents were higher in arils packaged in PM-MAP while ascorbic acid was slightly reduced. Antioxidant activities tested against FRAP and DPPH radical-scavenging activity increased across all types of MAP over storage duration. However, antioxidant activities were significantly higher in pomegranate arils packaged in PM-MAP due to O2-promoted biosynthesis of phenolics and anthocyanins which constitute the antioxidant properties. Overall, the results reported in this study showed that the use of PM-MAP in cold chain could be suitable for the preservation of physico-chemical quality, phytochemical contents and antioxidant properties of arils packaged in passive PM-MAP compared to clamshell and non-perforated packages during postharvest handling and storage. Perforating MAP films showed potential in preventing the incidence of in-package moisture condensation which is a common problem during postharvest handling and storage of fresh produce packaged inside non-perforated MAP. The results also showed the importance of keeping PM-MAP packs in closed refrigerated shelves to avoid cross contamination or ingress of foodborne pathogens.
AFRIKAANSE OPSOMMING: Perforasie-bemiddelde gewysigde-verpakking (PM-MAP) maak dit moontlik om polimeer films te optimiseer en om sodoende te kompenseer vir die versperring beperkings van die konvensioneel-gewysigde atmosfeer verpakking (MAP). Die doelwit is om die effek van PM-MAP en die duur van stoor op die fisioko-chemiese gehalte kenmerke, mikrobiale gehalte, fitochemikale (antisianien, fenolies en askorbiensuur) en antioksidant aktiwiteite van granaatarils van vars, minimaal geprosesseerde granate, te ondersoek (cv. Acco). Die effek van die aantal perforasies (0, 3, 6 en 9; Ø =0.8 mm) en stoortemperatuur (5, 10 en 15 ºC) op die waterdamp transmissie koers (WVTR, g/m2.day) van sintetiese ‘Polylid’ en biodegradeerbare (Nature flexTM) polymeriese films is ondersoek. Die resultate het bewys dat nie-perforeerde biodegradeerbare film by alle stoortemperature ’n hoër WVTR het, en dat by alle tipes film, ’n verhoogde aantal perforasies (van P-3 tot P-9) ’n hoër impak op WVTR het as ’n verhoogde stoortemperatuur (van 5 tot 15 ºC). Verder is die effek van PM-MAP op die fisiko-chemiese kenmerke, fitochemikale komponente en antioksidant aktiwiteite van vars, minimaal-geprosesseerde granaatarils bestudeer. Die granaatarils (100 g) is verpak in in polipropilien (PP) platkissies (10.6 x 15.1 cm2) en verseël met polimeer film, POLYLID®. Perforasies (0, 3, 6 en 9; Ø =0.8 mm) is aan die bo-end van die film aangebring en alle voorbeelde is vir 14 dae teen 5 ± 1 ºC en 95 ± 2 % relatiewe humiditeit. Die voorbeelde is met tussenposes van 3, 6, 9, 12 en 15 dae ontleed. Die ontleding het toetse vir Escherichia coli, aerobiese mesofiliese bakterië, suurdeeg en skimmel op tussernposes van 0, 6, 10 en 14 dae ingesluit. Die resultate bewys dat die komposisie van die gas beïnvloed word deur die aantal perforasies. Dit help om die vermindering in O2 met ’n ooreenkomstige toename in CO2 vlakke te balanseer en om dus toestande wat deur ’n gebrek aan suurstof veroorsaak is, te verhoed. Die totaal van oplosbare vaste stowwe, titreerbare suurgehalte en fermheid van die granaatarils is deur die PM-MAP verminder veral as dit vergelyk word met “clamshell trays”. Die kleur kenmerke het oor die algemeen dieselfde gebly by al die behandelings en dwarsdeur die stoortydperk. Die hoogste aantal aerobiese mesofiliese bakterië (5.5 log CFU/g), gis en skimmel (5.3 log CFU/g) is in die P-0 en P-9 verpakkings onderskeidelik opgemerk. Oor die algemeen is P-3 en P-6 beter in staat om die fisioko-chemiese kenmerke en mikrobiale gehalte van die granaatarils te behou. Die totaal van die fenoliese and antosianiin inhoud was hoër in granaatarils wat verpak is in PM-MAP maar die askorbiensuur was effens laer. Antioksdant aktiwiteite is getoets teen FRAP en DPPH aktiwiteite het by al die tipes van MAP tydens stoor vermeerder. Antioksidant aktiwiteite was egter heelwat hoër in granate wat in PM-MAP verpak is. Dit is die gevolg van die biosintese van fenolies en antosianins wat deur O2 in die hand gewerk word en wat die basis van antioksidant kenmerke vorm. Oor die algemeen toon die resultate van hierdie studie dat die gebruik van PM-MAP in die koue ketting geskik is vir die behoud van fisieko-chemiese gehalte, fitochemiese inhoud en antioksidant kenmerke van granaatarils wat in passiewe MAP verpak is, veral as dit vergelyk word met die vrugte wat in ‘clamshell’ en nie-geperforeerde verpakking tydens hantering na die oes en tydens stoor verpak is. Die perforeer van MAP films kan die voorkoms van die kondensasie in die verpakking verminder. Hierdie kondensasie is ’n algemene probleem tydens die hantering en stoor van vars vrugte wat in MAP sonder gaatjies verpak is. Die resultate toon ook hoe belangrik dit is om die PM-MAP verpakking in toe, verkoelde rakke te hou en om sodoende kruis-kontaminasie asook kontaminasie deur kieme wat in vrugte teenwoordig is, te voorkom.
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Das, Elif. "Effect Of Controlled Atmosphere Storage, Modified Atmosphere Packaging And Gaseous Ozone Treatment On The Survival Characteristics Of Salmonella Enteritidis At Cherry Tomatoes." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605337/index.pdf.
Full textAbstract:
iv
In recent years, outbreaks of infections associated with raw and
minimally processed fruits and vegetables have been reported. Possible
sources for contamination are irrigation water, manure, wash water, handling
by workers and contact with contaminated surfaces. Pathogens can occur on
raw and minimally processed produce at populations ranging from 103 to 109
CFU/g and able to survive and sometimes grow under various storage
conditions. The objective of this study was to analyse the growth/survival of
Salmonella Enteritidis at spot-inoculated or stem-injected cherry tomatoes
during passive modified atmosphere packaging (MAP), controlled
atmosphere (CA) and air storage at 7 and 22°C. Low density polyethylene (LDPE) with a package size of 10x10 cm2 for 25±
2 g tomatoes was used for MAP storage in which the gas composition equilibrated to 6% O2/ 4% CO2 and a carbon dioxide incubator was used for CA storage in which the CO2 level was monitored and maintained as 5% through the term of storage at 7 and 22°
C. During the research, the effect of ozone treatment (5-30 mg/L ozone gas for 0-20 min) was also considered for surface sanitation. The results demonstrate that S.Enteritidis can survive and/or grow during the storage of tomatoes depending on the location site of the pathogen on fruit, suspension cell density and storage temperature. During MAP, CA and air storage, S.Enteritidis with initial population of 7.0 log10 CFU/tomato survived on tomato surfaces with an approximate decrease of 4.0-5.0 log10 CFU/tomato in population within the storage period
however, in the case of initial population of 3.0 log10 CFU/tomato, cells died completely on day 4 during MAP storage and on day 6 during CA and air storage. The death rate of S.Enteritidis on the surfaces of tomatoes that were stored in MAP was faster than that of stored in air. Storage temperature was effective on the survival of S.Enteritidis for the samples stored at ambient atmosphere
cells died completely on day 6 at 7°
C and on day 8 at 22°
C. Stem scars provided protective environments for Salmonella
an approximate increase of 1.0 log10 CFU/tomato in stem-scar population was observed during MAP, CA and air storage at 22°
C within the period of 20 days. Cells survived with no significant change in number at 7°
C. The development of the microbial association in tomatoes was dominated by lactic acid bacteria (LAB). The pH values of the tomatoes changed approximately from 4.0 to 3.0 during the storage period. LAB grew well under all atmospheric conditions with or without the presence of S.Enteritidis. Gaseous ozone treatment has bactericidal effect on S.Enteritidis, inoculated on the surface of the tomatoes. 5 mg/L ozone gas treatment was not effective. 30 mg/L ozone gas treatment affected surface color.
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Oliveira, Ticiane Coelho Abreu de. "Estudo da qualdiade microbiolÃgica, quÃmica, fÃsico-quÃmica e sensorial de cenoura (Daucus carot, L.) submetida à tecnologia Sous vide produzida em escala industrial." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9248.
Full textAbstract:
The carrot is a crop rich in carotenoids, pro-vitamin A, minerals and carbohydrates, and is a food with high nutritional value. Brazil is among the five largest producers and consumers of carrot (Daucus carot L
.) in the world, concentrating its production in the Southeast. In search of products more attractive, practical, nutritious and healt hy, the consumer's sous vide technology is an alternative technology for the industry in providing food ready for consumption. The sous vide consists in cooking food packaged in plastic vacuum
-sealed, subjected to temperatures lower than 100ÂC for extended periods of time, chilled quickly and
stored under refrigeration. The aim of this study was to evaluate the quality and shelf life of carrots (
Daucus carot L.) diced submitted to sous vide technology, produced on an industrial scale. The samples were subje
cted to physical and chemical analysis and chemical,
microbiological and with three replications, with five repetitions of the products, and soon after processing by 2, 4, 6 and 8 weeks of storage (3ÂC). Sensory analysis was carried out on days 0 and 4 weeks, with a repeat. The results indicated a significant difference of 5% (p ≤0.05) in carbohydrate, protein, ash, titratable acidity and chromaticity between the carrot fresh carrot and processed by sous vide technology at time 0. In times of 2, 4, 6 and
8 weeks of storage at 3ÂC difference was significant (p ≤ 0.05) only for protein and total acidity. In
sensory analysis, no significant difference (p ≤ 0.05) in any of the attributes studied. It was also observed that the technology sous vide was effective in eliminating vegetative cells of micro-organisms pathogenic and spoilage, yet not been able to eliminate spores. The carrot
processed by sous vide technology retains its nutritional characteristics, sensory, chemical and microbiologically stable for up to eight weeks of storage at 3ÂC.A cenoura à uma olerÃcola rica em carotenÃides, prÃ-vitamina A, minerais e carboidratos, constituindo um alimento com alto valor nutritivo. O Brasil està entre os cinco maiores produtores e consumidores de cenoura (Daucus carot L.) do mundo, concentrando sua produÃÃo na regiÃo sudeste. Na busca de produtos mais atrativos, prÃticos, nutritivos e saudÃveis pelo consumidor, a tecnologia sous vide surge como uma alternativa tecnolÃgica para a indÃstria no fornecimento de pratos prontos para consumo. O sous vide consiste em cozinhar alimentos acondicionados em embalagens plÃsticas seladas à vÃcuo, submetidos a temperaturas inferiores à 100ÂC por longos perÃodos de tempo, resfriados rapidamente e armazenados sob refrigeraÃÃo. O objetivo desse trabalho foi avaliar a qualidade e a vida de prateleira de cenouras (Daucus carot L.) cortadas em cubos submetida a tecnologia sous vide, produzida em escala industrial. As amostras foram submetidas as anÃlises fÃsico-quÃmicas e quÃmicas, com trÃs repetiÃÃes e microbiolÃgicas, com cinco repetiÃÃes, dos produtos, logo apÃs o tecnologia e por 2, 4, 6 e 8 semanas de armazenamento refrigerado (3ÂC). A anÃlise sensorial foi realizada nos tempos de 0 e 4 semanas, com uma repetiÃÃo. Os resultados indicaram que houve diferenÃa significativa de 5% (p≤0,05) nos carboidratos, proteÃnas, cinzas, acidez total titulÃvel e na cromaticidade entre a cenoura in natura e a cenoura processada por tecnologia sous vide no tempo 0. Nos tempos de 2, 4, 6 e 8 semanas de armazenamento a 3ÂC houve diferenÃa significativa (p≤0,05) apenas nas proteÃnas e acidez total titulÃvel. Na anÃlise sensorial, nÃo houve diferenÃa significativa (p≤0,05) em nenhum dos atributos estudado. Observou-se tambÃm que a tecnologia sous vide foi eficiente na eliminaÃÃo de cÃlulas vegetativas de micro-organismos deteriorantes e patogÃnicos, porÃm nÃo foi capaz de eliminar esporos. A cenoura processada por tecnologia sous vide conservou suas caracterÃsticas nutricionais, sensoriais, quÃmicas e manteve-se estÃvel microbiologicamente atà oito semanas de armazenamento à 3ÂC.
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Lobaton-Sulabo, April Shayne S. "The effects of four packaging systems and storage times on the survival of Listeria monocytogenes in shelf-stable smoked pork and beef sausage sticks and whole muscle turkey jerky." Thesis, Kansas State University, 2009. http://hdl.handle.net/2097/14081.
Full textAbstract:
Master of ScienceDepartment of Food Science
Elizabeth A. E. Boyle
To validate how packaging and storage reduces Listeria monocytogenes (Lm) on whole muscle turkey jerky and smoked sausage sticks, four packaging systems, including heat seal (HS), heat seal with oxygen scavenger (HSOS), nitrogen flushed with oxygen scavenger (NFOS), and vacuum (VAC), and four ambient temperature storage times were evaluated. Commercially available whole turkey jerky and pork and beef smoked sausage sticks were inoculated with Lm using a dipping or hand-massaging method, respectively. There was no interaction on packaging and storage time on Lm reduction on smoked sausage sticks and an Lm log reduction of >2.0 log CFU/cm[superscript]2 was achieved in smoked sausage sticks packaged in HS, HSOS, and VAC. A >2.0 log CFU/cm[superscript]2 reduction was achieved after 24 h of ambient temperature storage, regardless of package type. NFOS was less effective in reducing Lm by more than 0.5 log CFU/cm[superscript]2 compared to HS, HSOS or VAC. After 30 d of ambient storage, Lm had been reduced by 3.3 log CFU/cm[superscript]2 for all packaging environments. In turkey jerky, Lm reduction was affected by the interaction of packaging and storage time. HS, HSOS, NFOS, or VAC in combination with 24, 48, or 72 h ambient temperature storage achieved <1.0 log CFU/cm[superscript]2. After 30 d at ambient temperature storage, Lm was reduced by >2.0 log CFU/cm[superscript]2 in HS and VAC, and could serve as a post-lethality treatment. Alternatively, processors could package turkey jerky in HSOS or NFOS in combination with 30 d ambient storage period as an antimicrobial process. Very little data has been published describing how packaging atmospheres affects Lm survival in RTE meat. The mechanism for Lm reduction under these conditions is not fully understood and additional research is needed.
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Mertlová, Tereza. "Analýza současného stavu a možnosti optimalizace logistického systému ve společnosti Unipetrol RPA." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-73913.
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The Master's Thesis deals with an analysis of logistic system in the Unipetrol RPA Company. The objective of this thesis is to detect possible bottlenecks and to identify possibilities to optimize the logistic system. The first part of the Master's Thesis characterizes the terms logistics, Supply Chain Management, logistic chain, lean management, outsourcing, further it deals with the area of storage facilities, packaging, transportation, handling and storage means. The second chapter contains introduction of the Company, the respective branch of industry, as well as international project ChemLog. The analysis of the Company logistic system itself is described in the third chapter. Analyzed are individual logistic processes within the Company related to polyolefins (polyethylene and polypropylene). At the end of this chapter, bottlenecks of the system are detected and subsequently, certain recommendations proposed, which should be considered.
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Vissa, Avanthi. "Effect of Raw lngredient Surface Area, Storage Time and Antioxidants on Color and Oxidative Stability of Ground Beef in 80% Oxygen Modified Atmosphere Packaging." DigitalCommons@USU, 2004. https://digitalcommons.usu.edu/etd/5510.
Full textAbstract:
Fresh beef packaged in high-oxygen modified atmosphere packaging (MAP) has longer red color stability than beef in oxygen-permeable polyvinyl chloride (PVC) film. However, fresh beef in high oxygen becomes rancid by 10 days storage at 2°C. Thus the objective of this study was to evaluate the effectiveness of various antioxidants (milk mineral, MM; sodium tripolyphosphate, STP; vitamin E, E) on color and thiobarbituric acid (TBA) values of ground chuck stored in 80% oxygen MAP for 14 days at 1° C. A preliminary experiment was also done to determine the effect of raw meat history (surface area during storage and storage temperature) on stability of ground beef in 80% oxygen MAP.
For the preliminary experiment, select beef clods ( 48 hrs postmortem) were cut 11 into trim or coarsely ground and stored frozen or at 2°C in vacuum packaging (VP) for 30 days. Raw meat was then finely ground and wrapped in PVC film or in 80% oxygen. For experiment 2, fresh beef clods were coarsely ground and antioxidants (0.75 or 1.5% MM; 0.25 or 0.5% STP; 50 or J 00 ppm vitamin E) were added, followed by fine grounding and packaging in 80% oxygen MAP.
Thiobarbituric acid assay was performed as a measure of rancidity. Hunter color L*, a*, b* values were measured on raw samples through the packaging film. Trim history greatly affected stability of beef in 80% oxygen MAP. VP refrigerated trim yielded ground beef with low oxidative and color stability compared to frozen trim. In comparison of antioxidants, 0.75% MM gave highest redness values (13-15) and lowest TBA values (< 0.5) after storage of ground beef in 80% oxygen MAP for J 4 days. STP-treated beef also had low TBA values(< 0.5) at 14 days storage but samples were less red (a* of J 0-J 2) than MM- treated samples. Samples with E were slightly better than controls, with redness values of 7.9 and J0.8, respectively. Thus, iron-chelating agents (MM and STP) were very effective for preventing rancidity and improving color stability in ground beef packaged in a high oxygen atmosphere.
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Saleh, Fatima, Susann Bartsch, and Jessica Steen. "Internal material handling at Volvo Construction Equipment Braås." Thesis, Växjö University, School of Management and Economics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-2424.
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Background: Material handling is a large part of a company´s internal work and represents between 15 % and 70 % of the total cost of a manufactured product. By improving the internal handling of material, more efficient distribution and manufacturing flows are possible. The material handling process is an input to the production and assembly process that has to be defined and mapped so that it can be improved. The material handling process studied at Volvo CE Braås includes goods receiving, storage, packaging as well as the order/delivery process to assembly, and will finish with the material transport to the assembly line.
Research questions: How can the material handling process, from goods receiving to assembly line, at Volvo CE in Braås be described by using VSM? What kinds of waste can be identified? By proposing a future-state map, how can the identified problems and waste be reduced or eliminated?
Methodology: This thesis is a descriptive case study and was conducted with a deductive approach. Data was collected by our own observations, personal interviews, statistics, benchmarking and questionnaire. The scientific credibility of this thesis was secured by for example using many sources, avoidance of assumptions, studying a common process and following standardized steps of the VSM tool.
Conclusions: The material handling process was described in the separated areas of goods receiving, storage and assembly line. Visualization was given in a current-state map. Five different kinds of waste were identified. Finally, suggestions of improvements were presented along with a future-state map.
Suggestions on future research: A more detailed VSM including information flow and lead times could be studied. Scenario simulations of critical areas within the material handling process could be preformed. Furthermore, an ABC classification of articles and storage locations can be done to optimize storage.
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Chan, Perochena Rocío Valery, and Estrada Martha Guissel Montalvo. "Actividades logísticas y su relación en la importación de productos farmacéuticos de la subpartida nacional 3004.90.24.00 durante el periodo 2014 - 2018 en el sector privado." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652473.
Full textAbstract:
En el Perú las importaciones de medicamentos oncológicos y VIH han venido creciendo en durante los años, a pesar de su alto valor. Este escenario se debe a la falta de inversión en I+D para la industria local, así como al incremento de pacientes de estas enfermedades.
Es por ello, que la presente investigación tiene como fin analizar las principales actividades logísticas y su relación con las importaciones de productos farmacéuticos de la subpartida nacional 3004.90.24.00 durante los años 2014 al 2018 en el sector privado. En primer lugar, se realizó una descripción de las variables en base a sus antecedentes y bases teóricas. En segundo lugar, para poder validar las hipótesis de la investigación se utilizó un enfoque cuantitativo, en base a un diseño no experimental, transversal y correlacional, para lo cual se elaboró una encuesta dirigida a los importadores representativos de medicamentos oncológicos y VIH. Finalmente, bajo resultados estadísticos se determinó que existe una relación positiva moderada fuerte entre las actividades logísticas con las importaciones de la subpartida nacional estudiada; asimismo, se pudo obtener resultados para cada subvariable de las actividades logísticas, es decir, transporte, almacenaje y embalaje, los cuales indicaron tener relación con las importaciones tratadas en la investigación.Imports of oncological drugs and HIV in Peru have been growing over the years, despite their high value. This scenario is due to the lack of investment in R&D for the local industry, as well as the increase in patients with these diseases. That is why the purpose of this research is to analyze the main logistics activities and their relation with imports of pharmaceutical products of national subheading 3004.90.24.00 during the years 2014 to 2018 in the private sector. First, a description of the variables was made based on their antecedents and theoretical bases. Secondly, in order to validate the research hypotheses, a quantitative approach was used, based on a non-experimental, cross-sectional and correlational design, for which a survey was conducted for representative importers of oncological drugs and HIV. Finally, under statistical results it was determined that there is a strong moderate positive relation between logistics activities with imports of the national subheading studied. Additionally, it was possible to obtain results for each subvariable of the logistical activities, that is, transportation, storage and packaging, which indicated that they were related to the imports treated in the investigation.
Tesis
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Molinari, Andréa Cristina Fialho. "Métodos combinados para preservar a qualidade pós-colheita do mamão \'Golden\' tipo exportação." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/64/64132/tde-01082007-155105/.
Full textAbstract:
Com o propósito de avaliar o efeito da combinação de tecnologias de conservação pós-colheita no armazenamento do mamão Golden, foram testados os seguintes tratamentos: embalagens de caixas de papelão (CP); CP + embalagem de PEBD - filme de polietileno de baixa densidade com 0,05mm de espessura (PE); CP + PEBD com 0,025m de espessura contendo mineral absorvedor de etileno (PEAbs); radiação gama nas doses de 0,4 kGy e 0,7 kGy; armazenamento refrigerado (10°C e 90% de umidade relativa) por 2, 5, 10, 15, 20, 25, 30 e 35 dias. Em cada um destes períodos, as amostras foram colocadas sob condições ambiente por cinco dias para amadurecimento fora das embalagens, simulando a etapa de comercialização do produto. Para avaliar o efeito dos tratamentos sobre a qualidade dos frutos foram estudados os seguintes parâmetros: - no primeiro ensaio experimental, incidência de doenças, cor da casca e perda de turgidez (análise visual); cor da casca e da polpa, perda de peso, firmeza da polpa, sólidos solúveis totais, acidez total titulável, pH, beta-caroteno e licopeno; e no segundo ensaio, análise sensorial para as combinações que obtiveram melhores resultados na primeira etapa da pesquisa. A principal causa de descarte de amostras foi incidência de doenças, principalmente a antracnose. As perdas de peso foram maiores nas amostras sem embalagens plásticas. O fator tempo foi a principal causa de variação sobre a firmeza da polpa, havendo interação significativa do mesmo com os tratamentos, embora não tenha havido efeito das combinações quando comparadas entre si. Observou-se efeito significativo (F = 95%) na interação das doses de irradiação (0,4 e 0,7 kGy) com o tempo de armazenamento, na coloração da casca dos mamões, independente do tipo de embalagem utilizado. Os frutos irradiados ao atingirem ao ponto de consumo, apresentavam coloração com maior uniformidade e um amarelo / alaranjado mais característico. Os valores médios variaram de 1,27 a 1,79 \'mü\'g/ml de polpa para beta-caroteno e de 19,16 a 23,90 \'mü\'g/ml de polpa para o licopeno, estas substâncias não foram afetadas significativamente (F a 95%) pelos tratamentos ou intervalos de estocagem. O mesmo foi observado para sólidos solúveis totais, acidez total titulável e pH que apresentaram as seguintes médias: 11,53 e 12,20 °Brix, 0,117 e 0,136 g de ácido cítrico/100g de polpa, 4,91 e 5,04, respectivamente. Na avaliação sensorial, os provadores não conseguiram detectar diferenças significativas nas amostras de mamões submetidas as diferentes combinações de tratamentos. Observou-se a ocorrência de sinergismo na combinação das técnicas utilizadas, sendo o maior período total de armazenamento (35 dias) obtido com a utilização do conjunto: caixa de papelão+PEabs+irradiação a 0,4 kGy, sem perda da qualidade pós-colheita dos frutos. Sendo, portanto, este o tratamento recomendado para os mamões \'Golden\' destinados à exportação para países com restrições quarentenárias para mosca das frutasWith the purpose of evaluating a combination of postharvest techniques on papaya Golden storage, the following treatments were investigated: carton boxes packaging (CP); CP + plastic bag of PEBD - low density polyethylene film, with 0.05mm of thickness (PE); CP + PEBD with 0.025mm of thickness impregnated with mineral ethylene scavenger (PEAbs); y-irradiation (0.4 kGy and 0.7 kGy); and refrigerated storage at 10°C e 90% of relative humidity for 2, 5, 10, 15, 20, 25, 30 and 35 days plus five days under environmental conditions to allow ripening and to simulate the product marketing. To evaluate the effects on fruit quality the following measurements were taken: - first experiment, disease incidence, skin color and loss of turgidity (as visual variables); skin and flesh color, weight loss, flesh firmness, total soluble solids, total titratable acidity, pH, lycopene and beta-carotene composition; - second experiment, sensorial analysis on samples submitted to the treatments with better results from the first experiment. Posharvest diseases were the main factor responsible for discarding fruits. Percentage of weight loss was higher on papayas stored without plastic packaging. Time affected the flesh firmness (F = 95%). However, there wasn\'t influence of the treatments on that parameter. A significant effect on skin color was observed with interaction between irradiation (0.4 and 0.7 kGy) and storage period. Once reached the edible stage, irradiated papayas presented more uniformity on skin color. For beta-carotene and Lycopene, the mean values were 1.27 to 1.79 and 19.16 to 23.90 \'mü\'g/ml of flesh, respectively. But those substances weren\'t affected by the combined methods or the time. The same behavior were observed for total soluble solids, total titratable acidity and pH (mean values of 11.53 to 12.20 °Brix, 0.117 to 0.136 g of citric acid/100g of flesh and 4.91 to 5.04, respectively). On sensory evaluation, the judges didn\'t get to detect significant differences among papayas submitted to different treatments. A synergism was verified on the techniques combination, with the best results obtained from the association of CP + PEabs + y-irradiation at 0.4 kGy, which reached a total storage period of 35 days. Thus, that is the posharvest hurdle technology recommend for exporting \'Golden\' papayas to markets with quarantine restrictions to fruit-flies
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Fernandes, Rafaella de Paula Paseto. "Estabilidade da carne de cordeiro em diferentes condições de armazenamento." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-11082011-135917/.
Full textAbstract:
Atualmente no Brasil a carne ovina é comercializada quase exclusivamente congelada. No entanto, praticamente não existem estudos no país sobre alterações na qualidade desta carne durante seu armazenamento. Com a crescente demanda do consumidor por produtos de maior conveniência, surge a necessidade de maiores estudos em relação à estabilidade de cortes cárneos ovinos estocados sob refrigeração, principalmente em decorrência de sua curta vida útil. Os objetivos deste trabalho foram avaliar a estabilidade da carne ovina quando estocada sob refrigeração e congelamento e se diferentes sistemas de acondicionamento em atmosfera modificada poderiam aumentar a estabilidade desta carne quando armazenada sob refrigeração. Foram realizados dois experimentos. No primeiro, lombos ovinos foram embalados a vácuo e armazenados sob refrigeração (4±1ºC) por 28 dias e congelamento (-18±1ºC) por 12 meses. No segundo, os cortes foram acondicionados individualmente em 3 diferentes sistemas de embalagem com atmosfera modificada: 1) Á vácuo (sistema tradicional); 2) Com injeção de gases na proporção 75% O2 e 25% CO2 e 3) Com injeção de 100% de CO2). Neste segundo experimento as carnes foram armazenadas sob refrigeração (1±1ºC) por um período de 28 dias. A estabilidade dos cortes foi avaliada por meio de análises físicas, químicas, microbiológicas e sensoriais, sendo que no segundo estudo, além destas análises também foi acompanhada a composição gasosa no espaço-livre. Foram realizadas três repetições de cada um dos estudos. A carne de cordeiro, nas diferentes temperaturas de estocagem e nos três sistemas de embalagens, apresentou-se estável ou com índices aceitáveis em relação à maioria dos parâmetros físicos e químicos avaliados e dentro dos padrões estabelecidos pela legislação brasileira para microrganismos patogênicos durante todo o período. No primeiro estudo, mesmo com uma redução significativa da maciez (de 3 para 8 Kg), a carne congelada continuou sensorialmente aceitável, com todos os atributos, inclusive a textura, recebendo notas em torno de 7 (\"gostei moderamente\"). Portanto, é possível afirmar que a carne de cordeiro apresenta vida de prateleira de no mínimo 12 meses quando armazenada à -18ºC. Em relação à avaliação da estabilidade do lombo ovino refrigerado, detectou-se um aumento elevado das contagens de psicrotróficos anaeróbios, atingindo valores da ordem de 107 UFC/g amostra já aos 14 dias. Esta carne foi avaliada sensorialmente apenas em relação aos atributos cor, aparência geral e aroma. Mesmo considerando as elevadas contagens de microrganismos psicrotróficos, os consumidores não detectaram alterações significativas nos atributos avaliados durante os 28 dias de armazenamento refrigerado. No segundo trabalho, os sistemas de embalagem com injeção de gases foram eficientes em reduzir a proliferação de microrganismos deterioradores quando comparados com o sistema tradicional de embalagem à vácuo. Em relação às diferentes composições gasosas, o sistema com 100% de CO2 apresentou menores contagens microbiológicas do que aquele com 75% O2 e 25% CO2, sendo possível concluir que o sistema de embalagem contendo 100% CO2 garantiu uma maior estabilidade durante 28 dias de armazenamento. No entanto, o lombo de cordeiro acondicionado nesta condição apresentou uma menor preferência sensorial da aparência em relação aos demais tratamentos durante todo o período avaliado.Nowadays, in Brazil, sheep meat is mainly commercialized as frozen meat. However, in the country studies on possible quality meat changes during frozen storage are scarce. In addition, the increasing consumer demand for higher convenience products supports the need of more studies on of sheep meat cuts stability stored under refrigeration, mainly due to its short shelf life. The objectives of this work were to evaluate the stability of sheep meat when stored under refrigeration and freezing as well as to evaluate different packaging systems under modified atmosphere and the effect of this technology on the meat stability when stored under refrigeration. In order to achieve these objectives, two experiments were performed. In the first study, sheep loins were vacuum packaged and stored under refrigeration (4±1ºC) for 28 days and freezing (-18±1ºC) for 12 months. For the second study, cuts were individually packed in three different atmospheres: 1) vacuum (traditional system), 2) With 75% O2 and 25% CO2 and 3) With 100% CO2. For second experiment, meat was stored under refrigeration (1±1ºC) for a period of 28 days. Stability of the cuts was evaluated by means of physical, chemical, microbiological and sensory analysis, while for the second study, there were also performed headspace gas composition along the storage. Three replications of each study were carried out. The lamb meat at different storage temperatures and the three packaging systems, presented good stability or acceptable indexes in relation to most physical and chemical parameters evaluated. Samples showed good microbiological stability according to standards established by Brazilian legislation for pathogenic microorganisms throughout the storage period. In the first study, there was a significant reduction in tenderness (3 to 8 kg), nevertheless, the frozen meat continued sensory acceptable, showing texture scores around 7 (like moderately). Therefore, it is clear that the lamb meat has a shelf life of at least 12 months when stored at -18ºC. In relation to evaluation of the stability of chilled lamb loin, it was detect a high increase counts of anaerobic psychrotrophic, reaching around 107 CFU/g at 14 days storage. For thies reason, this meat was sensory evaluated only in relation to attributes color, overall appearance and flavor. Even considering the high counts of psychrotrophic, the consumers did not detect significant changes in the attributes evaluated during the 28 days of refrigerated storage. For he second work, it was verified that the gas compositions applied were more effective in reducing the proliferation of deteriorative microorganisms when compared with the traditional vacuum packaging. The system with 100% CO2 presented lower microbiological counts than that with 75% O2 and 25% CO2. Thus the packaging system containing 100% CO2 assured greater stability during 28 days storage. However, the lamb loin packed in this condition presented a lower preference sensory appearance compared to other treatments during the evaluated period.
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Tokairin, Tatiane de Oliveira. "Caracterização e conservação pós-colheita de cambuci, fruto nativo da Mata Atlântica." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-24082017-134117/.
Full textAbstract:
Diversas mirtáceas são nativas dos biomas brasileiros, sendo que a Mata Atlântica é o local onde muitas das espécies desta família ocorrem e têm grande importância pela qualidade de seus frutos. Dentre as espécies do gênero, o cambuci [Campomanesia phaea (O. Berg.) Landrum] é apontado com grande potencial funcional e sensorial que pode ser explorado comercialmente, devido às suas características nutricionais e funcionais. Entretanto, a carência de informações técnicas sobre a espécie, aliada à falta de tecnologias adequadas à conservação in natura e processamento dos frutos, colocam em risco a exploração do seu potencial comercial e de consumo. Em decorrência desse panorama, os objetivos do presente trabalho foram: (1) avaliar a diversidade entre cambucizeiros originados de semente, quanto aos seus aspectos físicos e químicos, compostos bioativos e compostos voláteis, (2) determinar o ponto adequado de colheita e comportamento respiratório dos frutos e por fim, (3) investigar a influência da temperatura de armazenamento na qualidade e na fisiologia pós-colheita de cambuci, com o intuito de fornecer subsídios técnicos/científicos à exploração comercial desta frutífera. Os resultados da caracterização físico-química dos frutos e dos teores de voláteis revelaram diferenças entre as árvores matrizes, os locais de colheita e entre as safras dos anos de 2014 e 2015. O estádio de maturação 2, caracterizado por frutos maduros colhidos na planta, com coloração verde-amarelada e região equatorial levemente arredondada, foi definido como o ponto de colheita ideal para cambuci. Os frutos do E2 possuíam qualidade igual ou superior aos frutos dos outros estádios avaliados, tendo menor adstringência, conteúdo superior de ácido ascórbico e vida-útil pós-colheita acrescida em pelo menos 2 dias, por terem menor perda por podridões, maior firmeza da polpa e menor perda de massa frutos. Os frutos cambuci apresentaram padrão respiratório não-climatérico. Apresentaram também alteração da qualidade sensorial, ao longo dos dias após a colheita, entre os estádios de maturação, constatado pelo perfil dos compostos voláteis, tanto pela abundância de metabólitos, como pela nota aromática. Frutos mais verdes apresentam aromas herbáceo, etéreo ou pungente e à medida que amadureceram passaram a apresentar aromas frutados e canforados. O armazenamento dos frutos a baixa temperatura comprovou ser uma alternativa viável para a pós-colheita dos frutos de cambuci, contribuindo para a sua conservação, prolongando sua vida útil. Os resultados obtidos abrem perspectivas para o desenvolvimento da fruticultura do cambuci, haja vista a variabilidade genética entre os genótipos produtivos aqui demonstrada. Dessa forma, há subsídios para a implementação de programas de melhoramento da espécie com vistas ao aumento na produtividade dos plantios, atendendo à sua cadeia produtiva. Ademais, os resultados dão suporte para a definição de procedimentos de pós-colheita do cambuci, fundamentados em informações técnicas que garantem metodologia específica para a colheita e armazenagem dos frutos de cambuci. Portanto, os resultados descritos representam um avanço frente à definição de práticas de colheita e armazenagem dos frutos, garantindo assim a expansão da fruticultura da espécie.There are several Myrtaceae native to the Brazilian biomes, being the Atlantic Forest the place where many of them occur, having great importance for the quality of its fruits. Among the species of the genus, cambuci [Campomanesia phaea (O. Berg.) Landrum] has great functional and sensorial potential, being able to be exploited commercially due to its nutritional and phytotherapeutic characteristics. However, the lack of technical information about the species, coupled with the lack of appropriate technologies for in natura conservation and fruit processing, delay the exploitation of its commercial and consumption potential. Due to this background, the objectives of this study were: (1) assess the diversity among cambucizeiros originated by seeds and their physical and chemical quality, bioactive compounds and volatile compounds, (2) determine the appropriate maturity stage for harvest and respiration rate, (3) to investigate the influence of storage temperature on cambuci quality and postharvest physiology, with the purpose of providing technical/scientific subsidies to the commercial exploitation of this fruit. The results of the physicochemical characterization of the fruits and the volatile contents revealed differences between the matrix trees, harvesting sites and between the harvests of 2014 and 2015. The maturation stage 2, characterized by ripe fruits harvested in the plant, with a yellowish-green coloration and slightly rounded equatorial region, was defined as the ideal picking for cambuci. The fruits had an equal or higher quality than the fruits of the other maturity stages, with lower astringency, higher ascorbic acidcontent and postharvest life at least 2 days larger. These results were obtained because in this maturity stages, fruits had less rot loss, greater pulp firmness and fresh weight loss. The cambuci fruits showed a non-climacteric respiratory pattern. They also showed changes in the sensorial quality, along the days after harvesting and between the stages of maturation, verified by the volatile compounds, the abundance of metabolites and aromatic notes. Greener fruits have herbaceous, ethereal or pungent aromas, and as they mature, they have fruity and camphorated aromas. The fruits storage at low temperature proved to be a viable alternative for the postharvest of cambucis, contributing to its conservation, prolonging its shelf-life, without compromising its quality. The results obtained open perspectives for the development of cambuci produce, given the genetic variability among the productive genotypes demonstrated here. Thus, there are subsidies for the implementation of breeding programs of the species for increasing the productivity, considering their productive chain. In addition, the results support the definition of postharvest procedures for cambuci, foundations in technical information that guarantee specific methodology for the harvest and storage of cambuci fruits. Therefore, the results described here represent an advance in harvesting practices and storage of the cambuci fruits, guaranteeing the expansion of production of the species.