Tesi: "Sensory evaluation"

1

Deans, Gillian A. "Design and analysis of sensory evaluation experiments". Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240734.

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2

Rose, Grenville John, of Western Sydney Hawkesbury University, Faculty of Science and Technology e School of Food Science. "Sensory aspects of food preferences". THESIS_FST_SFS_Rose_G.xml, 1999. http://handle.uws.edu.au:8081/1959.7/130.

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Abstract (sommario):

Little is known about how liking for different foods develops from birth to adulthood. Although there are both cultural and sensory aspects to the development of food preferences, the focus of this study is on the sensory aspects of food preference development, in particular, preferences for meat. Two main aims are addressed : 1/. To develop a robust methodology that can be used to determine pre-literate and recently literate children's liking for different foods and the determinants of that liking. 2/. To investigate the effects of early experience with foods on later food preferences.Several tests were conducted and results noted. Overall the results of this thesis show that it is possible to gather reliable hedonic data from young, even pre-school children, and that it is possible that very early feeding experience has some influence on adults' food preferences.
Doctor of Philosophy (PhD)

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3

Ismail, Baraem. "Dates : physico-chemical characteristics, total quality and nutritional significance". Thesis, University of Central Lancashire, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275924.

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4

Krishnamurthy, Raju Chemical Sciences &amp Engineering Faculty of Engineering UNSW. "Prediction of consumer liking from trained sensory panel information: evaluation of artificial neural networks (ANN)". Awarded by:University of New South Wales. Chemical Sciences & Engineering, 2007. http://handle.unsw.edu.au/1959.4/40746.

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This study set out to establish artificial neural networks (ANN) as an alternate to regression methods (multiple linear, principal components and partial least squares regression) to predict consumer liking from trained sensory panel data. The study has two parts viz., I) Flavour study - evaluation of ANNs to predict consumer flavour preferences from trained sensory panel data and 2) Fragrance study ??? evaluation of different ANN architectures to predict consumer fragrance liking from trained sensory panel data. In this study, a multi-layer feedforward neural network architecture with input, hidden and output layer(s) was designed. The back-propagation algorithm was utilised in training of neural networks. The network learning parameters such as learning rate and momentum rate were optimised by the grid experiments for a fixed number of learning cycles. In flavour study, ANNs were trained using the trained sensory panel raw data as well as transformed data. The networks trained with sensory panel raw data achieved 98% correct learning, whereas the testing was within the range of 28 -35%. A suitable transformation methods were applied to reduce the variations in trained sensory panel raw data. The networks trained with transformed sensory panel data achieved between 80-90% correct learning and 80-95% correct testing. In fragrance study, ANNs were trained using the trained sensory panel raw data as well as principal component data. The networks trained with sensory panel raw data achieved 100% correct learning, and testing was in a range of 70-94%. Principal component analysis was applied to reduce redundancy in the trained sensory panel data. The networks trained with principal component data achieved about 100% correct learning and 90% correct testing. It was shown that due to its excellent noise tolerance property and ability to predict more than one type of consumer liking using a single model, the ANN approach promises to be an effective modelling tool.

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5

Kupongsak, Sasikan. "Food process control based on sensory evaluations /". free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3115564.

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6

Cerff, Jeanne. "Optimisation of kefir biomass and metabolite production in conjunction with sensory evaluation". Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52979.

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Thesis (MSc)--Stellenbosch University, 2002.
ENGLISH ABSTRACT: Developing countries such as South Africa are in dire need of nutritionally adequate dairy food and beverage sources that are ambient stable due to minimal access to refrigeration. One such product is Kefir, a naturally fermented milk beverage that originated in Caucasian China many centuries ago. The microorganisms responsible for fermentation of the milk are held together in a carbohydrate matrix in the form of small grains. These grains are then removed from the beverage prior to consumption, and added to fresh milk for new fermentations. This beverage holds great potential for large scale development due to the self-propagating nature of the grains, the lack of sophisticated equipment and knowledge necessary for production, and the appealing sensory characteristics of this beverage. This study was therefore performed as an initial investigation to determine the optimum fermentation conditions for large-scale grain production and optimal sensory appeal. Kefir grain production was found to be proportional to incubation temperature in the range studied (18°, 22°, 25° and 30°C), with maximum grain biomass increases of 500% for the Kefir incubated at 30°C over the 10 d trial. During fermentation of Kefir grains in milk, lactic acid and other metabolites are produced. Lactic acid results in coagulation of the milk, necessary to provide the characteristic texture and flavour of Kefir, as well as exerting a preservative effect. Lactic acid production was found to be strongly proportional to both incubation temperature and inoculum concentration. The samples containing 2% (w/v) Kefir grain inoculum concentration that were incubated at 25°C for 24 h were found to have optimum lactic acid levels for good quality Kefir (pH of 4.4 - 4.6 and TA of 1.0 - 1.15%). The other metabolites produced during Kefir fermentation are responsible for the specific flavour of Kefir, and include acetaldehyde, diacetyl, ethanol, acetone and 2-butanone. These compounds were studied using headspace gas chromatography over the fermentation period, which yielded good resolution and separation of all these compounds, however, only acetaldehyde, ethanol and acetone were found to be major metabolites in this study, These analytical results were then further compared to sensory results for key identified attributes, as obtained from a trained sensory panel, to enable recommendations for optimum fermentation conditions to be made. The studied attributes included sourness, sweetness, butteriness, creaminess, yoghurt flavour, cowiness, effervescence, yeastiness, smoothness and overall acceptability. It was apparent from this study that correlations between analytical and sensory data could be drawn, and that panellists were particularly accurate in detecting the attribute sourness resulting from the accumulated lactic acid in the Kefir. Overall acceptability also seemed to be intricately linked to the attribute creaminess, hence the regular literature references to full-cream Kefir as optimum for best sensory appeal. From this study, it was evident that Kefir with optimal sensory appeal is obtained with incubation for 18 h at moderate temperatures (22° or 25°C) and grain inoculum concentrations (0.8% w/v).
AFRIKAANSE OPSOMMING: In ontwikkelende lande soos Suid-Afrika, bestaan daar 'n groot behoefte aan voedsame suiwelprodukte wat stabiel is by kamer temperatuur aangesien 'n groot deel van die bevolking beperkte toegang tot verkoelingsfasiliteite het. Een so 'n produk is Kefir, 'n natuurlike gefermenteerde suiwelproduk wat sy oorsprong eeue gelede in China gehad het. Die mikroorganismes wat verantwoordelik is vir die fermentasie, is saamgebind in 'n koolhidraat matriks in die vorm van klein korrels. Hierdie korrels word verwyder uit die drankie voordat dit gedrink word, en word dan weer by vars melk bygevoeg vir 'n verdere fermentasie. Hierdie gefermenteerde produk het baie potensiaal vir massa-produksie, omdat die korrels natuurlik vermeerder, geen gesofistikeerde toerusting of kennis nodig is nie, en die finale produk hoogs aanvaarbare sensoriese eienskappe het. Die doel van die studie was om 'n inleidende ondersoek uit te voer om die optimum fermentasie toestande vir massakweking van korrels en die mees aanvaarbare sensoriese eienskappe te bepaal. Uit hierdie studie is gevind dat Kefirkorrel vermeerdering proporsioneel is tot die verhoging in inkubasie temperatuur in die gebied 18°, 22°, 25° en 30°C, met maksimum biomassa toenames van tot 500% vir Kefir wat vir 10 dae by 30°C geïnkubeer was. Gedurende fermentasie van Kefirkorrels in melk, word melksuur en ander metaboliete gevorm. Melksuur lei tot die verlaging van die pH van die melk, en veroorsaak stolling, wat noodsaaklik is vir die kenmerkende tekstuur en geur van Kefir, maar dien ook as 'n preserveermiddel. Daar is ook gevind dat melksuur produksie 'n direkte verband het met die inkubasie temperatuur en inokulum konsentrasie. Die monsters met Kefirkorrel inokulum konsentrasie van 2% (miv) wat vir 24 h by 25°C geïnkubeer is, het die optimale melksuur konsentrasies vir goeie kwaliteit Kefir bevat (pH van 4.4 - 4.6 en TA van 1.0 - 1.15%). Ander metaboliete wat belangrike geurkomponente van Kefir is, is asetaldehied, diasetiel, etanol, asetoon en 2-butanoon. Hierdie metaboliete is bepaal en geëvalueer met bodamp gaschromatografiese tegnieke gedurende die fermentasie, wat 'n goeie resolusie en skeiding gelewer het. In hierdie studie is slegs asetaldehied, etanol en asetoon as hoof Kefir metaboliete gevind. Die analitiese data is verder vergelyk met die sensoriese data van die hoof sensoriese komponente, soos bepaal deur 'n opgeleide sensoriese paneel, om die mees gunstigde fermentasie parameters te bepaal. Die geëvalueerde eienskappe was suurheid, soetheid, botterigheid, romerigheid, joghurt geur, koeismaak, gas inhoud, gisagtigheid, gladheid en algehele aanvaarbaarheid. Uit hierdie data is gevind dat daar wel 'n sterk korrelasie bestaan tussen die analitiese en sensoriese resultate, en dat paneellede in staat was om die suurheid, as gevolg van die gevormde melksuur, te bepaal. Algehele aanvaarbaarheid is definitief gekoppel aan romerigheid, daarom word volroommelk Kefir verkies bo die wat met afgeroomde melk berei is. Die data uit hierdie studie het ook getoon dat Kefir met optimale sensoriese eienskappe verkry is na 'n inkubasietyd van 18 h by "matige temperature" (22° of 25°C) en 'n Kefirkorrel inokulum van 0.8% (mIv).

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7

Chanadang, Sirichat. "Sensory evaluation and consumer acceptability of novel fortified blended foods". Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35459.

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Doctor of Philosophy
Food, Nutrition, Dietetics and Health
Edgar Chambers IV
Fortified blended foods (FBFs), which are the mixture of cereals and legumes fortified with micronutrients, have been widely used as supplementary foods for vulnerable populations such as infants and young children in developing countries around the world. The evaluation of current FBFs showed limited evidence on their effectiveness in treating childhood malnutrition, resulting the several recommendations on processing and formulation changes to improve their quality and ability to meet nutritional needs. Sensory properties are one of the important determinants for the success of the new FBFs. Therefore, sensory testing was conducted to determine the potential of novel FBFs to be used as supplementary food compared with FBF currently used in food aid programs. Descriptive sensory analysis was performed on novel FBFs along with the traditional FBF (Corn soy blend plus; CSB+) to determine sensory characteristics of each FBF. Results showed that novel FBFs had more pronounced toasted characteristics and higher sweetness than CSB+, due to the higher temperature during extrusion process and the addition of sugar in the novel formulation. In addition, novel FBFs that had higher amount of legumes (e.g. soybean, cowpea) in their formulations, especially for all sorghum cowpea blends, showed higher intensity in beany characteristics. Sensory shelf-life testing showed that novel FBFs could have shelf lives at least 2 years with no detection of off-note characteristics and these was comparable to the shelf life of the current FBF (CSB+). Sensory testing was also performed with target populations: children who eat the food and care givers who prepare it, during a 20-week field trial to determine the acceptability and preference of novel FBFs and current FBF. Results showed that all novel FBFs were highly preferred or accepted by children, even though, some of them might need longer time and more exposures to allow children to have more experience and be familiar with the food before being satisfied or preferred that food. In contrary, CSB+ that had bland flavor tended not to be well accepted and highly preferred by children compared to novel FBFs. Moreover, giving children more opportunities to consumed food prepared from CSB+ did not help to improve its acceptability or preference. Data from household visits and interview sessions showed that porridges prepared from novel FBFs required less cooking time than CSB+ and no additional ingredients needed to be added compared to CSB+ where sugar and milk were common additions. Finding from this research indicated that novel FBFs have high potential to be used successfully as supplementary food with comparable shelf life, and higher acceptability and preference to FBF currently used in food aid programs. In addition, the simple cooking of novel FBFs make them valuable to caregivers who have limited time and access to energy sources and nutrient-rich ingredients.

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8

Kim, Joseph. "Quantitative sensory testing for evaluation chronic arthritis or local anesthesia". Thesis, Boston University, 2013. https://hdl.handle.net/2144/12136.

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Thesis (M.A.)--Boston University
Background: Properly functioning sensory systems are crucial in perception of external stimuli. Different modalities such as touch, temperature, and pain can only be appreciated with intact sensory pathways from the peripheral receptors to the cerebral cortex via the spinal cord. Pain is a sensory response to noxious, tissue damaging stimuli. It is an essential protective response for survival. However, abnormalities in sensory function may lead to hyposensitization or hypersensitization to a stimulus, which may cause numbness or pain respectively. Juvenile Idiopathic Arthritis (JIA) is a condition characterized by inflammation of the joints, resulting in stiffness and pain. The etiology of JIA is not well known, and little is understood about the associated changes in sensory function that may be present. In this study, we use quantitative sensory testing (QST) as a validated measure to assess local and global changes in sensory function in JIA patients. [TRUNCATED]

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9

Katzir, Irena. "Sensory and dietary quality of fiber-beef blends". Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43898.

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Recently, there has been an increased interest in manufacturing high fiber Foods. Beef patties containing 1% Lupran (sweet lupin bran flour), 2% barley and 3% of both fibers (1% Lu + 2% Ba) and a control all-beef pattie were manufactured and comparatively evaluated by visual and sensory panels. Hypocholesterolemic effects were tested by in vivo studies. Rats were fed diets containing meat or meat-blends as the sole source of protein, fat, fiber and cholesterol. All the diets were isocaloric. At the point of purchase, the meat blends were different (P < 0.05) from the in their apparent amount exudate, fat to lean ratio and integrity. Less significant was the difference in color, both visual and objective, with the beef-barley blend tending to be darker and the beef-lupran product tending to be brighter within 14 days oF storage. The sensory panel scored meat-blends as significantly less beefy, more beany and grainy (P> 0.05). The grainy flavor of barley was especially detectable. Mouthfeel was not significantly altered (P> 0.05) but there was a tendency for the panel to score the barley blend as dryer and tougher than the control. However, these results were not confirmed by objective measurements. Cooking losses and quantity of measured exudate For meat blends were similar to the control. Neither lupran nor barley had a significant antioxidative effect. The meat blend with 3% fiber lowered the LDL fraction in rats relative to that of rats on control diets. However, the amount of added fiber was too low to significantly affect serum or liver cholesterol.
Master of Science

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10

Nakano, Kumiko. "Study on sensory evaluation instrument for describing comprehensive palatability and preference". Kyoto University, 2014. http://hdl.handle.net/2433/185213.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第17988号
農博第2035号
新制||農||1019(附属図書館)
学位論文||H26||N4813(農学部図書室)
80832
京都大学大学院農学研究科食品生物科学専攻
(主査)教授伏木亨, 教授保川清, 教授安達修二
学位規則第4条第1項該当

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11

NATALETTI, SARA. "Design And Evaluation Of Sensory Stimulation Patterns For Enhancing Spatial Awareness". Doctoral thesis, Università degli studi di Genova, 2021. http://hdl.handle.net/11567/1047490.

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Spatial awareness refers to our ability to develop knowledge about the surrounding environment and our relation with it. It is essential for people of all ages and constantly used in everyday activities. Typically, sensory and motor systems work cooperatively to acquire a complete and detailed representation of the external world. However, there are several health conditions that may affect the integrity of spatial awareness, including autism spectrum disorder (ASD) as well as injury or neurological conditions (e.g., amputation, spinal cord lesions, or stroke). In these cases, the lack of spatial awareness is associated with severe impairments in everyday activities. This work is about novel audio and tactile stimulation patterns for enhancing spatial awareness, with a specific focus on attention and manipulation deficits. Spatial awareness can be increased non-visually, through acoustical stimulation, for sources of interest that are distal from the body. Specifically, in the first part, I studied ways to augment the human sense of hearing with spatially filtered soundscapes that can improve speech reception thresholds in a noisy environment. The sensory augmentation pattern was tested on autistic children who exhibit abnormal performance on auditory-based tasks. In particular, they show significantly poorer speech reception in noise relative to their neurotypical peers. Using a novel spatial filtering, speech reception in children with ASD significantly increased compared to their typical hearing condition. This finding is important because this filtering technique was previously used only on neurotypical and hearing-impaired subjects. The results indicate that artificially modulating sounds perception may positively impact daily social activities that require communication in noisy environments, not only in sensory-disabled persons but also in children with attentional deficits. Spatial awareness can also be increased non-visually, using tactile stimulation, which is intimately linked to contact and manipulation tasks, for sources of interest that are proximal to the body. In the second part, I designed and assessed different tactile stimulation patterns that can be used to carry gestural information in the spatial and frequency domain, with applications in prosthetics for amputees and rehabilitation of post-stroke patients. Amputees and post-stroke patients suffer from impairments of both motor and somatosensory functions. While the functional recovery of upper extremities is one of the primary goals of rehabilitation programs, somatosensory deficits are often overlooked. Sensory substitution systems, providing tactile feedback, might facilitate manipulation capability and improve dexterity during grasping movements. As a first step, I evaluated the ability to determine the number of concurrent stimuli composing electrotactile feedback in healthy subjects. This study showed that temporal coding, and not total energy or duration, modulated the accuracy in numerosity judgment using electrotactile stimulation. As a second step, considering the body of evidence showing the modulation of vision on tactile perception, I investigated how the human’s enumeration abilityof tactile stimuli in a sensory substitution context could be influenced by vision. Results showed that vision, even when non-informative about the tactile stimulation, improves tactile numerosity judgment. The last part considered the link between tactile feedback and hand gesture. Normally, accurate integration of feedforward motor commands and sensory feedback is crucial for refined hand movements (sensory-motor loop). In the last study, I proposed a novel concept to close the sensory-motor loop. In particular, I provided the users with online feedback about the control signal generated by their muscle activation (i.e., myoelectric signal), allowing them to achieve an effective closed-loop system. More precisely, I assessed the extent to which frequency modulation of tactile stimulation can enhance the control of muscle activation reducing its variability, trying to find the most successful mapping between the generated myoelectric signal by the hand and its representation across the tactile array. Results showed that the addition of frequency modulation facilitates myoelectric control but only under specific feedback conditions. Summarizing, this thesis proposed and assessed new methods to artificially alter signals out of the body (acoustic feedback) and on the body (tactile feedback) aimed at increasing spatial awareness in healthy subjects and persons who lack sensory or attentional integrity. The results of this thesis can be interesting for engineers, psychologists, and rehabilitators. Having shown that spatial sound filtering techniques are beneficial for persons with ASD means that this technology may be used to support learning at school, behavioral therapy, and social interaction, which is typically lacking in ASD. Then, the proposed tactile patterns might be associated with occupational therapy to favor the motor recovery of the hand in post-stroke patients with severe impairment of hand sensitivity and mild or absent hand strength deficit. Moreover, these tactile patterns might offer one possible solution for closing the loop in the context of myoelectric prosthesis control, leading to more capable prosthetic limbs. The cross-modal findings can be applied in clinical rehabilitation. For instance, additional visual feedback might be used along with tactile stimulation to improve somatosensory performance in case of brain damage patients or to reduce pain intensity in chronic pain patients.

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12

Gabrielli, M. "CHEMICAL MARKERS FOR THE EVALUATION OF SENSORY AND ANTIOXIDANT PROPERTIES OF WINES". Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/230019.

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Sotolon (3-Hydroxy-4,5-dimethyl-2(5)-furanone) is a chiral lactone responsible for the oxidized flavour in fortified wines and wine produced by oxidative ageing. The perception threshold of the racemic mixture in wine is 8 – 10 μg/L and the flavour is reported as curry, aged honey, aged sake and fenugreek. Though it is considered a typical flavour note in Madera, Porto and Sherry, it is an off-flavour in dry white wine where its oxidative note is detrimental for the fresh taste and odour. The sotolon formation pathways, during winemaking, are affected by chemical and physical factors such as: oxygen concentration, storage temperature and time, reducing sugar concentration and antioxidant compounds concentration (e.g. sulphur dioxide or (GSH) glutathione). Due to the number of chemical and physical factors affecting the Sotolon formation in wine this compound has been suggested as chemical marker of white wine shelf-life. A fast, sensitive and easy to apply analytical method (UHPLC-UV) and it was applied to the evaluation of SO2-free Franciacorta DOCG wines in order to assess the effect of different disgorgement conditions (antioxidant additives, ageing time and temperature) on the sotolon formation. The sotolon concentration was measured in sparkling wine stored at 15°C and 25°C for 6 months added to three different antioxidant preparations (2 g/hL and 4 g/hL) potentially substituting the sulfur dioxide. Furthermore, we investigated the chemical and physical factors could affect the sotolon formation in synthetic wine. Model solution conitaing increasing concentration of pentoses, GSH, amino group, catechin, oxygen, ethanal, tartaric acid and iron are stored at two temperatures (70°C and 5°C) for five days in order to clarify the compositive factors affecting the sotolon synthesis in white wine. Finally, we compared the performances of analytical methods (HPLC-UV and UHPLC-MS) for sotolon quantification, which were previously developed. Separately, we developed a fast, sensitive and easy to apply analytical method (UHPLC-UV) for the biogenic amines (BAs) assessment in red wine treated with different malolactic fermentation condition (Spontaneous MLF; Inoculum and Co-inoculum techniques). Moreover was checked the trend of intra and extra-cellular glutathione and their effect on the aromatic matrix of South African Sauvignon blanc (Stellenbosch) must and wine during the alcholic fermentation and aging. The Must was treated with GSH and a GSH-enriched inactive dry yeast preparation (GSH-IDYs). The proposed analytical methods (UHPLC-UV; HPLC-UV and UHPLC-MS) provide a sample preparation faster and easier-to-apply than those previously reported for the routine analyses of sotolon. The methods (HPLC-UV; UHPLC-MS/MS; UHPLC-UV) were proved suitable for the determination of sotolon concentrations in white wine and in model solution under its sensory perception threshold. Two analytical methods compared (HPLC-UV; UHPLC-MS/MS) were successfully used for the screening of 70 commercial South African wines’ sotolon levels. The samples of Franciacorta sparkling wines treated with SO2 show the best protection against wine oxidation whereas the other commercial antioxidants tested caused detrimental effects due to the sotolon production. The phenolic composition of commercial antioxidants has influenced the production of sotolon. The sotolon formation tests carried out showed which sotolon can be formed by several formation pathways indeed it was generated under both reducing and oxidative conditions. Sotolon formation is enhanced by simultaneous presence of Fe++ and O2, of amino groups and of phenols. Glutathione inhibited the formation of sotolon only when it was simultaneously added with amino groups and phenols in an oxidizing environment or when it was present in oxidative conditions. Under anoxic conditions the sotolon formation test has been demonstrated that there is a high dependence between sotolon and reducing sugar contents, whereas tartaric acid and acetaldehyde didn't affect the formation of sotolon. The formation of sotolon in anoxic environment has not yet been clarified and further tests will be conduct to understand the role of tartaric acid, ethanol, ethanal and ribose on sotolon production in synthetic wine. The analytical method for the BAs quantification showed good linearity and repeatability and was able to quantify the ABs in red wine. The preliminary results concerning the different malolactic fermentation conditions, suggest that co-inoculum technique does not seem to prevent BAs formation in wine. The trial data on GSH (intra and extra-cellular) have yet to be processed and will be assessed in the future.

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13

Bergh, Alexandra Jane. "Characterisation of the sensory profile of Cyclopia intermedia and optimisation of fermentation parameters for improved product quality". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95908.

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Thesis (MScFoodSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: In light of the limited and inconsistent supply of good quality honeybush tea, a species-specific sensory profile and the physicochemical characteristics of Cyclopia intermedia (honeybush) tea were determined to ultimately establish the optimum fermentation parameters for this herbal tea on laboratory-scale and to validate these findings on commercial-scale. The characteristic sensory profile of C. intermedia can be described as sweet tasting and slightly astringent with a combination of “fynbos-floral”, “fynbos-sweet”, “fruity” (specifically “apricot jam”, “cooked apple”, “raisin” and “lemon/lemon grass”), “woody”, “caramel/ vanilla” and “honey-like” aromas. The flavour can be described as distinctly “fynbos-floral”, “fynbos-sweet” and “woody”, including hints of “lemon/lemon grass” and “hay/dried grass”. The results of the sensory study were used to create a C. intermedia sensory wheel and lexicon, and an elementary grading system that categorised samples into “good”, “average” and “poor” sensory quality was proposed. Physicochemical parameters, i.e. soluble solids (SS) content, absorbance as a measure of colour, and turbidity, were evaluated as possible rapid predictors of sensory quality. High SS content, absorbance and turbidity correlated strongly with “poor” sensory quality. A linear relationship existed between the physicochemical parameters. The effect of fermentation temperature (70, 80 and 90°C) and time (12, 16, 24, 36, 48 and 60 h) on the sensory and physicochemical characteristics of C. intermedia was determined on laboratory-scale. Increasing fermentation time increased the intensity of positive sensory attributes, while decreasing the intensity of negative sensory attributes. The SS content, colour and turbidity of infusions decreased with increasing fermentation time, while the SS content and turbidity of infusions increased with increasing fermentation temperature. Fermentation at 90°C for 36 h on laboratory-scale produced C. intermedia with the best sensory properties, while preserving the SS content and colour of infusions. Fermentation at 70°C and 80°C required longer fermentation times for development of positive sensory attributes. Fermentation at 90°C was subsequently validated on commercial-scale. Laboratory-scale fermentation of the same batches of plant material was also carried out concurrently to allow direct comparison of the scale of fermentation on tea quality. Commercial-scale fermentation, despite increased variability as a result of increased batch volumes and heating difficulties, produced C. intermedia of “good” sensory quality after 24 and 36 h of fermentation. Increasing fermentation time had little effect on the SS content and colour of infusions of tea produced on commercial-scale, but turbidity increased significantly after 36 h. Thus, to produce C. intermedia with consistently good quality on commercial-scale, fermentation at 90°C for 24 to 36 h is recommended. Increasing fermentation time past 48 h should be avoided to prevent turbidity and the development of sensory attributes characteristic of over-fermented tea. However, due to the large variability of commercial-scale honeybush tea production, it is recommended that each batch be monitored between 24 and 36 h to determine when optimum fermentation has been obtained.
AFRIKAANSE OPSOMMING: Beperkte en wisselvallige beskikbaarheid van goeie gehalte heuningbostee noodsaak die optimisering van fermentasie parameters vir Cyclopia intermedia. Optimisering van fermentation parameters is op laboratorium skaal gedoen, gevolg deur validasie van die parameters op kommersiële skaal. Vooraf is die spesie-spesifieke sensoriese profiel en die fisies-chemiese eienskappe van C. intermedia tee bepaal. Die kenmerkende sensoriese profiel van C. intermedia kan beskryf word as soet en effens vrank met 'n kombinasie van "fynbos-blomagtige", "fynbos-soet", "vrugtige" (spesifiek "appelkooskonfyt", "gekookte appel", "rosyntjie” en “suurlemoen/sitroen gras"), "houtagtige", "karamel/vanilla" en "heuningagtige" aromas. Die smaak kan beskryf word as "fynbos-blomagtig", "fynbos-soet" en "houtagtig", met 'n tikkie "suurlemoen/sitroen gras" en "hooi/gedroogde gras". Die resultate van die sensoriese studie is gebruik om 'n C. intermedia sensoriese wiel en leksikon, asook 'n basiese graderingstelsel wat tee monsters in "goeie", "gemiddelde" en "swak" sensoriese kwaliteit klassifiseer, te ontwikkel. Fisies-chemiese parameters: oplosbare vastestof (SS) inhoud; absorbansie as 'n maatstaf van kleur; en troebelheid, is geëvalueer as moontlike indikasies van sensoriese kwaliteit. Hoë SS inhoud, absorbansie en troebelheid waardes het sterk met "swak" sensoriese kwaliteit gekorreleer. 'n Lineêre verwantskap bestaan tussen die fisies-chemiese parameters en kwaliteit. Die effek van fermentasie temperatuur (70, 80 en 90°C) en -tyd (12, 16, 24, 36, 48 en 60 h) op die sensoriese en fisies-chemiese eienskappe van C. intermedia is op laboratorium skaal bepaal. Verlenging van fermentasie tyd het die intensiteit van die positiewe sensoriese eienskappe verhoog, terwyl dit die intensiteit van negatiewe sensoriese eienskappe verminder het. Die SS inhoud, kleur en troebelheid van die tee het met verlengde fermentasie tyd afgeneem, terwyl die SS inhoud en troebelheid met verhoging van fermentasie temperatuur toegeneem het. Fermentasie by 90°C vir 36 h op laboratorium skaal het tee met die beste sensoriese eienskappe geproduseer, met behoud van die SS inhoud en kleur. Fermentasie by 70°C en 80°C het 'n langer fermentasie tyd vir die ontwikkeling van positiewe sensoriese eienskappe vereis. Fermentasie by 90°C is daaropvolgens op kommersiële skaal uitgevoer, met gelyktydige laboratorium skaal fermentasie van dieselfde plantmateriaal lotte om die direkte effek van die skaal van fermentasie op tee kwaliteit te bepaal. Kommersiële fermentasie, ten spyte van verhoogde wisselvalligheid as gevolg van groot volumes tee en probleme met verhitting, het tee van "goeie" sensoriese kwaliteit na fermentasie periodes van 24 en 36 h geproduseer. Verlenging van fermentasie tyd het min uitwerking op die SS inhoud en kleur van kommersiel gefermenteerde tea gehad, maar troebelheid het beduidend na 36 h toegeneem. Fermentasie by 90°C vir 24 - 36 h word gevolglik aanbeveel om tee met goeie gehalte op kommersiële skaal te produseer. Fermentasie vir langer as 48 h moet vermy word om troebelheid te voorkom en die ontwikkeling van sensoriese eienskappe kenmerkend van oor-gefermenteerde tee te vermy. As gevolg van faktore wat groot variasie in kommersiële skaal heuningbostee produksie kan teweegbring, word aanbeveel dat elke produksielot tussen 24 en 36 h gemonitor word om die optimum fermentasie tyd te bepaal.

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14

Temple, Elizabeth C., of Western Sydney Hawkesbury University e Faculty of Science and Technology. "Aspects of the development of the sense of taste in humans". THESIS_FST_xxx_Temple_E.xml, 1999. http://handle.uws.edu.au:8081/1959.7/61.

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Very little research has been conducted on the development of taste perception in humans. Therefore there is a lack of knowledge, first, about how children perceive taste, especially when compared to what is known about how adults experience taste, and second, about the functioning and development of the gustatory system, including when the system is fully mature and functioning in an adult-like manner. The aims of this thesis were (i) to investigate the growth pattern of the tongue throughout childhood / adolescence, and (ii) to determine the state of maturity of some of the aspects of the sense of taste in mid-childhood. Overall, the data in this thesis indicate that children respond similarly to adults with regard to single-point measures of sensitivity and perceived intensity, but there are some differences in the overall temporal experience of taste, from onset of perception through to extinction, and the way in which it is perceived by adults and 8-9 year old children. The latter
Master of Science (Hons)

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15

Johnson, Daryan Stefon. "Protective effects of titanium dioxide packaging modification on sensory and oxidative changes in milk over 35 day shelf-life". Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/49695.

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Milk is often packaged in translucent containers providing little protection against flavor degradation from light. The effectiveness of TiO2 modifications of high density polyethylene (HDPE) packaging in affecting light-induced oxidation of extended shelf-life milk (2% total fat) and omega-3 fatty acid enriched milk (2% total fat) was studied. Packaging effectiveness was determined by assessing product quality, including changes in flavor, measuring changes in volatile compounds, thiobarbituric reactive substances and riboflavin concentrations. Products were evaluated over a 35-day shelf-life when stored under fluorescent light (2200 lux) at 4"C. HDPE packaging included clear (no TiO2) serving as control (light exposed: no light barrier, light protected (foil overwrap) and three different TiO2 levels (low, medium, high) for the experimental treatments (total of five packaging treatments). TBARS was a good predictor of the perception of changes in sensory characteristics in 2% milk.. Under the experimental conditions used, a TBARS value of 1.3 mg/L could be considered the limiting sensory threshold for oxidized milk. Riboflavin concentration decreased by 10.5% in the light-protected control over 36 days and 28.5% in the high TiO2 packaged 2% milk, but losses were greater than 40% for all other packages. In omega-3 enriched milk, the high TiO2-HDPE package provided greater protection of sensory quality and riboflavin than clear, low and medium TiO2 packaging. However riboflavin decreased by 28% even in the light protected control which is a higher loss than observed in 2% fluid milk without omega-3 lipids. TBARS was greater than 4 mg/L in all products, including the light-protected control within three days, suggesting that oxidative stability was low. Omega-3 milk packaged in clear HDPE package exceeded MDA of 3 mg/L by day 7, suggesting the milk would have changes in sensory quality related to oxidation. The high TiO2 package protected riboflavin concentration from degradation and controlled MDA concentration the best of the TiO2 treatments through the test period in both fish oil enriched and non-enriched products.
Master of Science in Life Sciences

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16

Potts, Hayley Lynn. "Oxidation barrier and light protective packaging properties for controlling light induced oxidation in milk". Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/80441.

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Fluorescent light exposure has well documented negative effects on fluid milk through oxidation reactions. A shift to light-emitting diode (LED) lights in retail dairy cases has occurred due to increased energy efficiency, but the effects of LED light on fluid milk are not known. The objective was to study the interaction of light protective additives (LPA) with a high oxygen barrier package under fluorescent and LED lighting conditions simulating a retail refrigerated dairy case. The extent of oxidation in 2% milk packaged in polyethylene terephthalate (PET) packages with different light interference properties (UV barrier, 2.1% titanium dioxide (TiO2) LPA, 4.0% TiO2 LPA, 6.6% TiO2 LPA) under light exposure up to 72h was compared to control packages (light-exposed, light-protected). Chemical measures of oxidation included dissolved oxygen content, formation of secondary lipid oxidation products, riboflavin degradation, and volatile analysis by electronic nose. Changes in dissolved oxygen content were associated closely with oxidation changes in milk over 72h. PET with 6.6% TiO2 was the most successful package, based on triangle test methodology, protecting milk sensory quality similar to light-protected milk through 8h LED light exposure. Based on a 9-point hedonic scale, (1=dislike extremely, 9=like extremely), consumers liked milk stored under LED light more (α=0.05; 6.59 ± 1.60) than milk stored under fluorescent light (5.87 ± 1.93). LED light is less detrimental to milk quality than fluorescent light and PET with high levels of TiO2 can protect milk quality for short periods of time under typical retail storage conditions.
Master of Science in Life Sciences

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17

Keogh, Grant Alexander. "The influence of the placement and removal of fixed orthodontic appliances on sensory detection threshold response of teeth as measured by an electric pulp tester". Thesis, The University of Sydney, 1990. http://hdl.handle.net/2123/4835.

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18

Knoth, Sharon K. "Essential accommodations for students with sensory impairments : perceptions from the field". Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1354646.

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This thesis explored standardized assessment practices and analyzed accommodations commonly provided to address the unique needs of students with a sensory impairment. Current assessment practices in Indiana result in well below average scores on the Indiana Statewide Testing for Educational Progress - Plus (ISTEP+) and the Graduation Qualifying Examination (GQE) for students who have a sensory impairment. Using a mixed-method of qualitative and quantitative processes, the researcher postulated that if assessment processes were equitable for this population of students, their scores should approximate the normal distribution seen in the overall state totals for the total school population; albeit with a slightly lower trajectory. Reasoning being that the overall population of students with a sensory impairment spans from students with high ability to students with multiple disabilities. Through a literature review and meta-analysis on the topic of assessment, surveys and discussions with varied local experts, and interviews with state and national experts in the sensory areas represented, this study sought to establish a framework for accommodating this population of students on standardized assessments. Using descriptive analysis procedures, the various data sets brought forth 25 qualities or practices that the diverse experts agreed should be in place when assessing this population of students. The data reflected a high level of consensus among parents, teachers, state, and national experts regardless of region of state represented. The data also reflected consensus across sensory subgroups (blind, deaf, deafblind, hard of hearing/cochlear implant, and low vision). The research concluded with a modified confirmatory factor analysis of the 25 qualities with the state-dictated permissible accommodations published in the test guidance manual. This analysis revealed less than half of the perceived best practices were in place for the current state-mandated assessment system. Suggestions for improving accommodation options on future assessment procedures and the prospective for further research were offered.
Department of Special Education

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19

Hart-Schubert, Patrice. "An evaluation of sensory comfort components of survey questionnaires used for indoor environment problems in buildings". Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/45051.

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The efficacy of indoor environment evaluation is, in part, a function of the reliability and validity of the different measures used. This thesis presents results of a study, conducted in a building without known problems, which compares the reliability and validity of sensory comfort components from three well-known survey questionnaires. A review of literature reveals that sensory comfort theory draws upon many disciplines including, hedonics, psychometrics, and olfaction theory. The fundamental domains thermal, air quality, lighting, and acoustics and their dimensions are identified. The conceptual model integrates these theories underlying human response to sensory comfort.

The research questions involved in the selection of survey questionnaires are explored by examining sixteen indoor environment survey questionnaires. A meta-evaluation reveals that these questionnaires have three major functions, proactive, reactive, and re-evaluative studies.

Finally, the methods used to analyze survey questionnaires for reliability and validity are examined. An analysis of variance shows that the order in which questions were presented did not affect responses. The reliability of the measures tested ranged from poor to good. Examination of content and face validity by expert and untrained judges demonstrates inconsistencies in common or accepted meanings of the measures considered in evaluating the indoor environment. Analysis of construct validity indicates that not all survey questionnaire variables were categorized under their expected dimensions.

Contrary to advice found in the literature, this thesis suggests that the practice of combining items from different questionnaires is problematic. Finally, in buildings with known problems we can expect a relatively high degree of reliability and validity. However, the utility of such questionnaires in inventorying and assessing buildings without known problems will prove to be questionable.
Master of Urban and Regional Planning

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20

Hamilton, Alexander. "Non-invasive imaging techniques and evaluation of sensory neuronal protection by N-acetylcysteine". Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/noninvasive-imaging-techniques-and-evaluation-of-sensory-neuronal-protection-by-nacetylcysteine(552b129a-5491-45b6-9f9d-c9dcff2c3e43).html.

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Background & Objectives: The potential benefits of adjuvant pharmacotherapy with N-acetylcysteine and acetyl-L-carnitine to reduce the amount of primary sensory neurons in the dorsal root ganglion (DRG) which die by apoptosis after peripheral nerve injury has been previously established. However, the duration of NAC therapy sufficient to achieve neuroprotection is unknown. Establishment of clinical trials of NAC/ALCAR therapy is hindered by relatively poor existing methods of assessment of neuronal populations and nerve regeneration in human subjects. Magnetic Resonance Imaging (MRI), a non-invasive modality, has been demonstrated in a pilot study to provide volumetric analysis of rat L4 DRG after sciatic nerve transection; detecting DRG volume reductions which reflect neuronal loss. Further, MRI has been reported to detect changes occurring in peripheral nerves distal to the site of injury, corresponding to axonal degeneration and subsequent regeneration. High Frequency Ultrasound (HFUS) is a new, high resolution imaging modality, not previously applied to the study of animal or human peripheral nervous system. Experiments were designed to test the duration of NAC treatment needed to achieve a neuroprotectant effect; to further evaluate the MRI DRG imaging protocol under interventional experimental conditions and in vivo; to investigate the ability of MRI and HFUS to visualise murine sciatic nerve and its response to injury and to assess the ability of HFUS to visualise human digital nerves in the hand. Further, a pilot study investigating the effect of NAC and ALCAR on primary sensory neurons in tissue culture was carried out to assess the neurotrophic effect of these agents in vitro. Methods: 1. Groups of rats underwent sciatic nerve transection, and NAC treatment for 7, 14, 30 or 60 days. At 60 days post injury neuron counts from L4 and L5 DRG were assessed histologically using a stereological optical fractionator analysis, and compared to the contralateral noN-axotomised DRG. 2. Animals from treatment groups were MRI scanned after two months to measure the L4 DRG volume bilaterally. A single animal was also scanned under anæsthesia and after death. 3. Numerous MRI techniques were used to scan rats after sciatic nerve crush, division and intraneural injection of contrast, attempting to identify the nerve and its response to injury. 4. Normal and injured rat sciatic nerve and intact human digital nerve were assessed by HFUS. 5. Cultured DRG neurons were exposed to a range of ALCAR/NAC doses or NGF, with assessment of cell survival and neurite formation at 24h. Results: 1. Neuronal death was related to duration of NAC treatment; with losses of 20%, 9%, 4% & 0% after treatment for 7, 14, 30 and 60 days respectively. 2. MR measured L4 DRG volume reduction correlated well with neuron loss. In vivo MRI scanning is feasible; however images are subject to motion artefact distortion, precluding accurate quantification. 3. The rat sciatic nerve could not reliably and consistently be identified by MRI in this model. 4. High frequency ultrasound can image sciatic nerve and its branches and human digital nerve with good resolution and can detect neurotmesis and axonotmesis grade injurys. 5. Non-toxic in vitro NAC/ALCAR dosage regimens have been defined, but do not affect neuron survival or neuritogenesis in the absence of NGF. Conclusions: 1. One month treatment with NAC post neurotomy prevents death of the majority of axotomised neurons. Apoptosis is prevented rather than delayed for some neuronal populations by NAC treatment. 2. MRI is a valuable objective tool, and DRG volume serves as a proxy measure of neuronal loss, fit for translation to human studies. 3. In vivo MRI DRG imaging requires motion compensation techniques such as respiratory gaiting. 4. Further investigation is needed to facilitate murine sciatic nerve imaging with MRI in this model, but HFUS easily demonstrates two grades of peripheral nerve injury, and is proposed for investigation of human digital nerve trauma. 5. The neuroprotective and regenerative effects of NAC/ALCAR on primary sensory neurons in vivo can not be replicated by direct treatment of isolated neurons in culture.

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21

Boza, Arauz Andrea. "Evaluation of Chemical, Physical, and Sensory Properties of Tortillas Prepared from Nixtamalized Oats". BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/9058.

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Background and objectives: While alkaline nixtamalization has historically been used for corn, this process may have application in other cereals. Drawbacks to wider use include the lengthy steep time, as well as the volume of alkaline wastewater produced. This study evaluated a novel, waste-effluent-free nixtamalization process for oat (Avena sativa) masa, and compared properties of oat masa and tortillas prepared with 1, 1.5 and 2% lime, with and without steeping. Findings: A minimal water-addition, 45-min, simmering process, without steeping, was effluent-free, and produced oat tortillas comparable to those produced using a traditional overnight steep. The pH increased significantly with increasing lime content (r=0.982). Consumer overall-liking scores did not significantly differ across treatments, though appearance scores were significantly higher for 2% lime samples (p<0.05), which were significantly darker and more yellow, based on L* and b* values. Masa adhesiveness means ranged from 1.49-1.52 N, with no significant differences between the no-steep treatments. Higher lime addition (1.5-2%) in the no-steep process significantly improved tortilla flexibility, based on extensibility and rollability scores, though tortilla rupture force did not vary significantly across treatments. Tortilla rollability scores at 3-days were lowest (x=1.1 + 0.31, indicating less cracking) for the 1.5-2% lime no-steep treatments, which were significantly better than the steeped treatment (x=3.7 + 0.48). Consumers rated the steeped sample as significantly less flexible. B-vitamins were negatively impacted by increasing lime, while calcium increased significantly with lime addition. Conclusions: The no-steep, effluent-free nixtamalization process produced oat tortillas with good masa and tortilla texture, which were not significantly different in consumer liking to tortillas produced via a traditional process. Significance and novelty: This research suggests nixtamalization can be applied to other grains in a shorter, environmentally-friendly process, with broader commercial applicability.

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22

Vierck, Kelly. "Evaluation of the role of marbling texture on beef palatability". Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35777.

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Master of Science
Department of Animal Sciences and Industry
Travis G. O'Quinn
The objective of this research was to evaluate the role of marbling texture on beef palatability, muscle histology, and collagen characteristics of beef strip loin steaks. Beef strip loins (n = 117) were selected from three quality grade treatments [Top Choice (Modest[superscript 00] – Moderate[superscript 100] marbling), Low Choice (Small[superscript 0] – Small[superscript 100] marbling), and Select (Slight[superscript 0] – Slight[superscript 100] marbling)] to equally represent three different marbling texture groups: fine, medium and coarse, via visual appraisal with the USDA marbling texture standards. Consumers (n = 104) rated all marbling texture groups similar (P > 0.05) for tenderness, juiciness, flavor, and overall liking, as well as rated a similar (P > 0.05) percentage of samples from each marbling texture group acceptable for each palatability trait. Moreover, consumers indicated no preference (P > 0.05) among marbling texture groups for visual desirability or likelihood to purchase. There were no differences (P > 0.05) among marbling texture treatments for Warner-Bratzler shear force, slice shear force, and pressed juice percentage. However, trained sensory panelists rated coarse marbled steaks higher (P < 0.05) than fine or medium marbled steaks for both beef flavor intensity and sustained juiciness as well as higher (P < 0.05) for initial juiciness than medium textured steaks. This minimal impact on palatability was further supported through evaluation of muscle histology and collagen traits. Marbling texture did not affect collagen characteristics, as coarse marbled steaks were similar (P > 0.05) to both fine and medium marbled steaks for soluble collagen, insoluble collagen, and total collagen content. Furthermore, all marbling texture groups (fine, medium, and coarse) performed similarly (P > 0.05) during the peak thermal transition phase of the perimysial fraction of collagen. However, marbling texture impacted (P < 0.05) adipocyte cross-sectional area, where coarse steaks had larger adipocytes in comparison to fine marbled steaks, but medium marbled steaks were similar (P > 0.05) to both coarse and fine marbled steaks. Similarly, quality grade affected adipocyte size, as Top Choice and Low Choice possessed larger (P < 0.05) adipocytes than Select steaks. However, marbling texture did not impact (P > 0.05) perimysial thickness. Additionally, marbling texture did not affect the percentage of myosin heavy chain (MHC) Type I fibers within each steak. However, medium marbled steaks possessed a greater (P < 0.05) percentage of MHC Type 2A fibers than both fine and coarse marbled steaks. The opposite trend was displayed in the percentage of MHC Type IIX fibers, as fine and coarse marbled steaks possessed more (P < 0.05) MHC Type IIX fibers in comparison to medium marbled steaks. There were no differences (P > 0.05) among quality grades for fiber type or marbling texture and quality grade for fiber cross-sectional area. Results from this study indicate marbling texture has minimal impact on eating quality and muscle histology; therefore coarse marbled carcasses should not be excluded from current and future branded beef programs.

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23

Apelman, Linnea. "Hur beskrivs sensoriska egenskaper inom deskriptiv analys? : En kvantitativ tvärsnittstudie av artiklar publicerade 1974-2019". Thesis, Umeå universitet, Institutionen för kost- och måltidsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-179774.

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Bakgrund Deskriptiv sensorisk analys (DSA) syftar till att beskriva sensoriska egenskaper (attribut) hos livsmedelslprodukter. En bedömarpanel analyserar ett produktprov genom att identifiera, namnge och mäta intensiteten hos ett antal attribut. Syfte Syftet med undersökningen var att studera hur attribut identifieras, beskrivs och presenteras inom vetenskaplig tillämpning av DSA. Metod Sjuttiofyra artiklar, publicerade i vetenskapliga tidskrifter mellan 1974 och 2019, analyserades kvantitativt med hjälp av deskriptiv statistik. Sjutton variabler användes för datainsamling. Samband mellan variablerna analyserades med hjälp av statistiska tester. Resultat Av artiklarna var 96 % publicerade i tidskrifter utan specifik inriktning mot sensorisk analys. I två tredjedelar av artiklarna tillämpades generisk deskriptiv analys (GDA). I fler än hälften av artiklarna avvek panelen från vad som rekommenderas kring bedömarantal eller tid för träning. I snitt användes 1,4 ord för namngivning av attributen. I hälften av artiklarna definierades inte attributen. I två tredjedelar av artiklarna presenterades inte några referensprodukter för att illustrera skalstegen. I tre fjärdedelar av artiklarna presenterades attributen i metodbeskrivningen. Meddelandelen substantiv var 68,2 % och 31 % adjektiv. En måttlig negativ korrelation mellan andelen substantiv och tiden för träning av bedömarpanelen var statistiskt signifikant. Slutsats I många vetenskapliga studier utförs DSA utan att gällande rekommendationer kring bedömarpanelen följs. I artiklar publicerade i vetenskapliga tidskrifter presenteras attributen inprecist nog att ifrågasätta användbarheten hos resultaten. Att ge den kvalitativa delen av undersökningen, identifiering och namngivning av attributen, status resultat skulle kunna öka intresset för att definiera attributen och illustrera skalstegen, vilket är en förutsättning för att tolka det kvantitativa resultatet (intensitetsmätningen) på ett meningsfullt sätt.
Background Descriptive sensory analysis (DSA) aims to describe the sensory attributes of food products. A panel of assessors analyze a sample of the product to identify and name a set of attributes and estimate their intensity. Objective The aim of the study was to research how attributes are identified, described and presented in the scientific use of DSA. Method By using descriptive statistics, 74 articles published in scientific journals between 1974 and 2019 were analyzed quantitatively. Data collection was conducted using 17 variables. Correlations between variables and differences between groups were analyzed using statistical tests. Results Of the articles 96 % were published in non-sensory-specific journals. Generic descriptive analysis (GDA) was used in two thirds of the articles. In more than half of the articles the number of assessors, or the time spent on assessor training, differed from what is recommended. An avarage of 1.4 descriptive words were used to name each attribute. In half of the articles no definitions of the attributes were given. In two thirds of the articles no reference products were presented to illustrate the attributes or different points of the scale. In three quarters of the articles the attributes were presentet in the section of method description, and not the results. The avarage share of nouns was 68.2 % and 31 % adjectives. A moderate negative correlation between the share of nouns and the time spent on panel training was significant. Conclusion Sometimes DSA is used without panel recommendations being followed. There are scientific articles where the sensory attributes are presented vaguely enough to question the usability of the results. To interperet naming of the sensory attributes as a qualitative results could motivate a more defined presentation, which would benefit the quantitative result (intensity assesment) by explaining what is meassured.

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Prado, Mirian Souza. "Elaboração de um refrigerante sabor laranja com adição de isolado proteico de soro de leite". Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/621.

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Atualmente o consumidor está bastante preocupado com a saúde, porém não está disposto a comprometer o sabor do alimento a ser consumido, assim o produto deve conter os ingredientes que propiciem o seu “bem-estar”, de modo a garantir os benefícios, sem prejudicar as características sensoriais. Desse modo, foi desenvolvida uma bebida tipo refrigerante sabor laranja com adição de isolado proteico de soro de leite, envasada em PET (Poli Tereftalato de Etileno) e armazenada em temperatura ambiente por 90 dias. Buscou-se estabelecer uma produção simples para ser facilmente adaptável nas linhas de processo de produção de refrigerante tradicional. Foram realizadas periodicamente durante o armazenamento em temperatura ambiente, análises físico-químicas, microbiológicas e sensoriais do produto. Os resultados da análise sensorial tiveram boa aceitabilidade, situando-se entre os termos hedônicos “gostei moderadamente” e “gostei muito”. A análise físico-química apresentou pH 3,53, 11,5 °Bx e 224 mg de ácido cítrico por 100 mL de bebida e com a seguinte composição proximal: proteínas 0,501%, umidade 88,9%, cinzas 0,084% e carboidratos 10,5 %. Durante o período de armazenamento a bebida obteve ausência de micro-organismo. Os resultados mostraram que este produto é estável, quando armazenado em temperatura ambiente por 90 dias. Desse modo, conclui-se que a bebida elaborada constitui uma alternativa na introdução de proteína de soro de leite no refrigerante, assim se tornando uma bebida com o valor nutricional superior e com mesmos valores de calorias comparados com refrigerante e alguns sucos de laranjas encontrados no mercado consumidor.
Currently consumers are very concerned about health, but is not willing to compromise the flavor, so the product must contain ingredients that provide your "wellness", to ensure the benefits of the drink without harming the sensory characteristics. Thus, we developed a type soda drink orange flavor with added protein isolate, whey, bottled in PET (poly (ethylene terephthalate)) and stored at room temperature for 90 days. We attempted to establish a production process simple to manufacture easily adaptable refrigerant in process lines. Were performed periodically during storage at room temperature, physico-chemical, microbiological and sensory product. The analysis results showed good sensory acceptability, standing between the hedonic terms "like moderately" and "like very much". The physical-chemical analysis showed pH 3.53, 11.5 °Bx and 224 mg citric acid per 100 ml of beverage and having the following composition hundredth: 0.501% protein, 88.9% moisture, ash 0.084 and carbohydrate 10,5%. During the storage period the beverage obtained absence of micro-organism. The results showed that this product is stable when stored at room temperature for 90 days. Thus, it is concluded that an alternative beverage prepared in the introduction of whey protein in the refrigerant, thereby becoming a beverage with superior nutritional value and with the same amounts of calories compared with refrigerant and some orange juices found in consumer market.

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25

Swaney-Stueve, Marianne. "Descriptive analysis by children, inexperienced and experienced adults, and comparisons among the groups /". free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3036863.

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26

Zadeh, Seyed Amirsaleh Saleh, e Jean Greyling. "The selection and evaluation of a sensory technology for interaction in a warehouse environment". Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/13193.

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In recent years, Human-Computer Interaction (HCI) has become a significant part of modern life as it has improved human performance in the completion of daily tasks in using computerised systems. The increase in the variety of bio-sensing and wearable technologies on the market has propelled designers towards designing more efficient, effective and fully natural User-Interfaces (UI), such as the Brain-Computer Interface (BCI) and the Muscle-Computer Interface (MCI). BCI and MCI have been used for various purposes, such as controlling wheelchairs, piloting drones, providing alphanumeric inputs into a system and improving sports performance. Various challenges are experienced by workers in a warehouse environment. Because they often have to carry objects (referred to as hands-full) it is difficult to interact with traditional devices. Noise undeniably exists in some industrial environments and it is known as a major factor that causes communication problems. This has reduced the popularity of using verbal interfaces with computer applications, such as Warehouse Management Systems. Another factor that effects the performance of workers are action slips caused by a lack of concentration during, for example, routine picking activities. This can have a negative impact on job performance and allow a worker to incorrectly execute a task in a warehouse environment. This research project investigated the current challenges workers experience in a warehouse environment and the technologies utilised in this environment. The latest automation and identification systems and technologies are identified and discussed, specifically the technologies which have addressed known problems. Sensory technologies were identified that enable interaction between a human and a computerised warehouse environment. Biological and natural behaviours of humans which are applicable in the interaction with a computerised environment were described and discussed. The interactive behaviours included the visionary, auditory, speech production and physiological movement where other natural human behaviours such paying attention, action slips and the action of counting items were investigated. A number of modern sensory technologies, devices and techniques for HCI were identified with the aim of selecting and evaluating an appropriate sensory technology for MCI. iii MCI technologies enable a computer system to recognise hand and other gestures of a user, creating means of direct interaction between a user and a computer as they are able to detect specific features extracted from a specific biological or physiological activity. Thereafter, Machine Learning (ML) is applied in order to train a computer system to detect these features and convert them to a computer interface. An application of biomedical signals (bio-signals) in HCI using a MYO Armband for MCI is presented. An MCI prototype (MCIp) was developed and implemented to allow a user to provide input to an HCI, in a hands-free and hands-full situation. The MCIp was designed and developed to recognise the hand-finger gestures of a person when both hands are free or when holding an object, such a cardboard box. The MCIp applies an Artificial Neural Network (ANN) to classify features extracted from the surface Electromyography signals acquired by the MYO Armband around the forearm muscle. The MCIp provided the results of data classification for gesture recognition to an accuracy level of 34.87% with a hands-free situation. This was done by employing the ANN. The MCIp, furthermore, enabled users to provide numeric inputs to the MCIp system hands-full with an accuracy of 59.7% after a training session for each gesture of only 10 seconds. The results were obtained using eight participants. Similar experimentation with the MYO Armband has not been found to be reported in any literature at submission of this document. Based on this novel experimentation, the main contribution of this research study is a suggestion that the application of a MYO Armband, as a commercially available muscle-sensing device on the market, has the potential as an MCI to recognise the finger gestures hands-free and hands-full. An accurate MCI can increase the efficiency and effectiveness of an HCI tool when it is applied to different applications in a warehouse where noise and hands-full activities pose a challenge. Future work to improve its accuracy is proposed.

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27

Nygren, Tobias. "Sensory evaluation and consumer preference of wine and food combinations : influences of tasting techniques /". Örebro : Örebro universitetsbibliotek, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-56.

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28

Arding, Fredrik. "Sensory evaluation and quality assessment of an alternative inner coating film in yogurt cartons". Thesis, Linköpings universitet, Teknisk biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119767.

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The dairy food industry is continuously striving towards products with higher quality and longer shelf-life available to the customer at low prices. Arla Foods in Linköping, Sweden, is currently investigating the possibilities of changing the material in yogurt packaging containers by replacing the currently used carton with a different and cheaper alternative. A successful switch will give the company an economical advantage without affecting the sensory attributes (smell, taste, sight, and consistency), aroma profile or other important trademarks of the yogurt. This study is designed to examine and compare yogurt that has been stored in different packaging cartons, one coated with a single-layered low-density polyethylene (LDPE) and one coated with a currently used multi-layered ethylene-vinyl alcohol (EVOH). The study was based on the analysis and measurement of sensory attributes performed by experts, physical properties in laboratory and chemical composition in GC-FID/MS together with a discriminative test where a group of people would identify any difference between the yogurts. Together, these analyses would provide an explanation about any differences between the packaging materials by connecting physical, chemical and/or sensory characteristics. The collected results would give a better and more comprehensive picture than each analysis would do separately. The results from the study show that there is a difference between yogurts stored in LDPE-based containers and yogurts stored in EVOH-based containers and that the product was chemically affected, mainly by the level of oxygen in contact with the food. The overall assessment is that the largest difference was discovered in the taste.

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29

Gruenfelder, Catherine A. "Sensory evaluation of heart-healthy foods enriched with omega-3 fats from fish oil". Thesis, College of Saint Elizabeth, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1555163.

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A diet rich in omega-3 fats has been shown to reduce the risk of cardiovascular disease. Long chain omega-3 fats found in fatty fish are especially important to cardiovascular health. Consumption of these fats is low, in part because there are few natural sources. This has led to the development of omega-3 fortified foods. Currently available fortified foods demonstrate conflicting nutritional information. Addition of omega-3 fats to an otherwise unhealthy food is perceived by consumers as an advertising gimmick. Mistrust of food companies and confusing ingredient labels negatively impact sales. Careful nutritional guidance, combined with proper sensory analysis, is critical to developing omega-3 fortified food products that are consistent with medical recommendations. Results from this study indicate that a therapeutic dose of fish oil (1000 mg per serving) can be added to two heart-healthy foods without adversely affecting sensory qualities.

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30

Castelo, Paula Catarino. "The influence of a fun packaging on children’s sensory evaluation of a healthy product". Master's thesis, NSBE - UNL, 2013. http://hdl.handle.net/10362/11620.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
This study aims at deepening the knowledge about the influence of packaging on children, more specifically about the impact it has on the post-consumption evaluation they do of the products. The experiment was done through individual interviews to 101 children in Portugal, between 7 and 10 years-old, using a paired comparison technique. Children had to choose between the apples of two different packages - one fun, targeted at children and one more simple and adult-like; although they did not know that inside the package it was the same apple on both. The results suggested that the fun packaged apple tastes better and is more likely to be requested at the supermarket. However, no inferences could be done in terms of differences in the evaluation of smell and sweetness of both apples. Moreover, it was found that the influence on children that live in the rural region is smaller than on those that live in the more urbanized area. In this sense, and since the study was done using a fruit, these findings may reinforce the use of packaging as a tool to promote healthier eating habits on children and they also show its importance in-store and their role in influencing children’s decisions and perceptions.

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31

Van, Wyk Juliette. "The inhibitory activity and sensory properties of kefir, targeting the low-income African consumer market". Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51989.

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Thesis (MSc Food Sc )--Stellenbosch University, 2000.
ENGLISH ABSTRACT: The rapid urbanisation of the African population has led to the establishment of large low-income communities in and around almost every major town and city in South Africa. Several factors prevent these people from producing or obtaining their traditional fermented milk drink, Maas (Amasi), often resulting in the occurrence of malnutrition in low-income urban African communities. A product with the potential to satisfy the demand for a fermented milk product is Kefir. Kefir, a self-carbonated fermented milk, is commonly manufactured by fermenting unpasteurised or pasteurised milk with re-usable Kefir grains. These Kefir grains consist of a combination of mainly lactic acid bacteria and yeasts. Neither Kefir, nor Kefir grains are as yet marketed in South Africa, thus creating an excellent opportunity to launch these products locally. It is often difficult for the low-income communities to obtain high quality unpasteurised or pasteurised milk, resulting in a serious health risk. The inhibitory activity of Kefir towards certain spoilage and pathogenic microorganisms was, therefore, studied. Strains of Escherichia coli, Staphylococcus aureus, Bacillus cereus, Usteria monocytogenes and Clostridium tyrobutyricum were inoculated (10 ³ - 10 ⁴ cfu.ml⁻¹ ) into pasteurised milk together with Kefir grains (18 gram per litre) and incubated at 25°C. Uninoculated milk samples and milk samples inoculated only with test organisms served as controls. Growth of all the test organisms were inhibited substantially (>-99.9%) in Kefir over the 30 h incubation period and substantial reductions in microbial log cycles were observed for many of the organisms. This coincided with a steep decrease in pH (6.57 - 4.06) and increase in titratabie acidity (0.20 - 0.72%). If Kefir is eventually marketed to low-income urban African consumers, it will have to compete with Maas and, therefore, comparative sensory testing of Kefir and Maas was conducted. The differences in the sensory properties of Kefir, 'laboratory' Maas (representing traditional Maas) and commercial Maas (containing thickener, colourants and flavourants) were determined by a trained panel. These characteristics were identified as "yeasty" and "cowy" tastes (p < 0.05), "effervescence" (p < 0.01), as well as "sourness," "creaminess" and "smoothness" (p < 0.001). The effect of different incubation temperatures (25°, 30° and 35°C) on the Kefir sensory properties was studied to simulate the effect of the large temperature variations that would be found in the dwellings of low-income African urbanites. The "sourness" and "creaminess" of the Kefir was found to increase with increase in incubation temperature but no strong off-flavours were found to develop. Sensory preference testing was conducted by consumer panels consisting of panellists of different ages and population groups to indicate whether the specific panels significantly prefer Kefir, commercial Maas or laboratory Maas. It was found that commercial Maas was significantly (p < 0.001) preferred to Kefir by young African urbanites. Adult Africans, who presumably still have traditional taste preferences, however, equally (p > 0.05) preferred Kefir and laboratory Maas, identifying this segment of the African population as the appropriate starting target market for Kefir. Kefir and laboratory Maas were also tested for preference by a wider panel consisting of people (aged between 18 and 25) representing the different population groups in South Africa. Kefir and laboratory Maas were preferred equally (p > 0.05) by all the groups. Several arguments supporting Kefir marketing to the low-income urban African population of South Africa have been identified. These include: Kefir's ease of preparation; the re-usability of Kefir grains and subsequent affordability; good packaging, distribution and storage possibilities; Kefir's acceptability by lactoseintolerant individuals; high nutritional value; the inhibitory activity of Kefir against potential spoilage and pathogenic organisms and subsequent enhanced safety and keeping ability; and Kefir's acceptable refreshing taste.
AFRIKAANSE OPSOMMING: Die toenemende verstedeliking van Swart Suid-Afrikaners het gelei tot die vestiging van groot lae-inkomste gemeenskappe in en om die meeste groot dorpe en stede. Verskeie faktore verhoed dat hierdie gemeenskappe hul tradisionele gefermenteerde melk, naamlik Maas (Amasi), self kan maak of koop. Dit lei dikwels tot wanvoeding onder lae-inkomste stedelike Swart verbruikers. Kefir het die potensiaal om te voorsien in die vraag na 'n gefermenteerde melk produk in lae inkomste stedelike Swart gemeenskappe. Kefir is 'n selfgekarboneerde, gefermenteerde melk wat vervaarding word deur die fermentasie van ongepasteuriseerde of gepasteuriseerde melk met herbruikbare Kefirkorrels. Hierdie Kefirkorrels bestaan uit 'n kombinasie van hoofsaaklik melksuurbakterieë en giste. Kefir en Kefirkorrels word glad nie in Suid-Afrika bemark nie, en bied 'n fantastiese geleentheid om hierdie produkte plaaslik bekend te stel. Dit is dikwels moeilik om hoë kwaliteit ongepasteuriseerde of gepasteuriseerde melk in lae-inkomste gemeenskappe te verkry. Die risiko om siektes deur die verbruik van hierdie melk op te doen, bestaan dus. Om hierdie rede is die inhiberende effek van Kefir teenoor spesifieke bederf- en patogeniese bakterieë bestudeer. Rasse van Escherichia coli, Staphylococcus aureus, Bacillus cereus, Usteria monocytogenes en Clostridium tyrobutyricum is geïnokuleer (10 ³ - 10 ⁴ cfu.ml⁻¹) in gepasteuriseerde melk tesame met Kefirkorrels (18 gram per liter) en geïnkubeer by 25°C. Melkmonsters wat slegs geïnokuleer is met die toetsorganismes het as kontroles gedien. Die groei van al die toetsorganismes is substansieël geïnhibeer (>-99.9%) in Kefir gedurende die 30 h inkubasieperiode. Substansiële afnames in logsiklusgetalle is waargeneem vir baie van die organismes. Dit het gepaard gegaan met 'n skerp afname in pH (6.57 - 4.06) en toename in titreerbare suurheid (0.20 - 0.72%) vir die Kefirmonsters gedurende die 30 h inkubasieperiode. lndien Kefir bemark word aan lae-inkomste stedelike Swart verbruikers sal dit moet kompeteer met Maas. Vergelykende sensoriese toetse is dus uitgevoer. Die verskille in die sensoriese eienskappe van Kefir, 'laboratorium' Maas (verteenwoordigend van tradisionele Maas) en kommersiële Maas (wat verdikker, kleur- en geurmiddels bevat) is bepaal deur 'n opgeleide paneel en geïdentifiseer as die" "gis-" en "koeismake" (p < 0.05), die "gasserigheid" (p < 0.01) asook die "suurheid", "romerigheid" en "gladheid" (p < 0.001) van die monsters. Die effek van verskillende inkubasietemperature (25°, 30° en 35°C) op die sensoriese eienskappe van Kefir is bestudeer om die effek van die groot temperatuurvariasies wat in laeinkomste behuising mag voorkom, te simuleer. Daar is bevind dat die "suurheid" en "romerigheid" van Kefir toeneem met verhoging in inkubasietemperatuur terwyl geen afsmake ontwikkel nie. Sensoriese voorkeurtoetse is deur verbruikerspanele van verskillende ouderdomme en bevolkingsgroepe uitgevoer om te bepaal of die spesifieke panele 'n beduidende voorkeur toon vir Kefir, laboratorium Maas of kommersiële Maas. Daar is bevind dat stedelike Swart jongmense kommersiële Maas beduidend (p < 0.001) bo Kefir verkies. Swart volwassenes met verwagte tradisionele smaakvoorkeure het egter Kefir en laboratorium Maas ewe veel verkies (p > 0.05). Hierdie segment van die Swart bevolking is dus die geskikte teikenmark vir die bekendstelling van Kefir. Voorkeur vir Kefir en laboratorium Maas is ook getoets deur 'n paneel (ouderdom 18 - 25 jaar) wat bestaan uit mense van verskillende bevolkingsgroepe. AI die groepe het Kefir en Maas ewe veel verkies (p > 0.05). Verskeie argumente ten gunste van die bemarking van Kefir aan lae-inkomste stedelike Swart gemeenskappe in Suid-Afrika is geïdentifiseer. Dit behels die volgende: die gerief van Kefirvervaardiging; die herbruikbaarheid van Kefirkorrels en gevolglike bekostigbaarheid; goeie verpakkings-, verspreidings- en opbergingsmoontlikhede; Kefir se aanvaarbaarheid vir laktose-intolerante individue; Kefir se hoë voedingswaarde; die inhiberende aktiwiteit wat Kefir teenoor potensiële bederf- en patogeniese organismes het en die gevolglike verhoging in veiligheid en rakleeftyd van melk; en Kefir se aanvaarbare verfrissende smaak.

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Modlich, Jessica D. "The Design and Evaluation of a Dynamic Compression Vest for Children with Autism". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306842036.

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33

Ratau, Mmaphuti Abashone. "Chemometrics, physicochemical and sensory characteristics of pearl millet beverage produced with bioburden lactic acid bacteria pure cultures". Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2773.

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Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2018.
The aim of this study was to evaluate the physical, chemical and sensory characteristics of non-alcoholic pearl millet beverage produced using isolated and purified cultures of bioburden lactic acid bacteria (LAB). Traditional non-alcoholic pearl millet beverage (TNAPMB) was produced through spontaneous fermentation. The slurry was fermented for 36 h at 37°C while monitoring the microbial growth at 3 h interval. LAB were grown on deMan, Rogosa and Sharpe agar and identified using Vitek 2 system. The initial numbers of LAB were 7.04 log cfu/ml and increased to 8.00 log cfu/ml after 21 h. The beverage was dominated by LAB and contaminants and their survival was in succession. LAB from the genera Leuconostoc, Pediococcus, Streptococcus and Enterococcus were the main fermenting species in TNAPMB. Pearl millet extract (PME) was produced by hydrating pearl millet flour (PMF) with water (1:10, PMF:Water). To the mixture sprouted rice flour (10%), ground ginger (10%) and pectin (0.6%) were added. Stable PME was used in the production of plain non-alcoholic pearl millet beverage (PNAPMB). PME was pasteurized at 98°C for 30 min, hot filled and cooled to 25°C. The fluid was inoculated with Leuconostoc mesenteroides, Pediococcus pentosaceus and Enterococcus gallinarum each at 0.05, 0.075 and 0.1%, respectively, using factorial design and fermented for 18 h at 37°C. The pH of the beverage ranged between pH 3.32 and pH 3.90. L. mesenteroides, P. pentosaceus, E. gallinarum, the interaction between L. mesenteroides and P. pentosaceus and the interaction between L. mesentoroides and E. gallinarum had a significant effect (p ˂ 0.05) on the pH of PNAPMB except the interaction between P. pentosaceus and E. gallinarum (p = 0.631). The total titratable acidity (TTA) of the beverage ranged from 0.50 to 0.72%. All cultures had a significant influence (p ˂ 0.05) on the TTA of the beverage with the exception of the interaction between L. mesenteroides and E. gallinarum (p = 0.102). However, Monte Carlo simulation showed that E. gallinarum caused an increase in the pH and a decrease in the TTA of the beverage. During fermentation, the pH of the beverage is desired to decrease while the TTA increases, hence E. gallinarum was removed. The interaction between L. mesenteroides and P. pentosaceus at 0.05% and 0.025%, respectively produced an acceptable PNAPMB with potential for commercialization. Furthermore, moringa supplemented non-alcoholic pearl millet beverage (MSNAPMB) was produced by adding 4% of moringa (Moringa oleifera) leaf powder extract during the production of PNAPMB. The physicochemical, nutritional, microbial (LAB) and sensory characteristics of the PNAPMB, MSNAPMB and TNAPMB were determined. LAB were significantly (p < 0.05) affected by the fermentation period and increased from 3.32 to 7.97 log cfu/ml and 3.58 to 8.38 log cfu/ml in PNAPMB and SNAPMB, respectively. The pH of PNAPMB decreased from pH 5.05 to pH 4.14 while the pH of MSNAPMB decreased from pH 5.05 to pH 3.65 during the 18 h fermentation. The growth of LAB during fermentation had a significant effect (p < 0.05) on the pH of the beverages. The TTA increased from 0.14 to 0.22% and increased from 0.17 to 0.38%, in PNAPMB and MSNAPMB, respectively. The TTA of the beverage was affected significantly (p < 0.05) by the 18 h of fermentation. The protein content was 1.62, 2.17 and 1.50% in PNAPMB, MSNAPMB and TNAPMB, respectively. PNAPMB sample was deemed acceptable in comparison to the MSNAPMB. The total colour difference (ΔE) was 5.91 and 10.60 in PNAPMB and MSNAPMB, respectively in comparison to the TNAPMB. Volatile compounds with beneficial effect such as anti-inflammatory and anti-pathogenic properties were identified in the beverages. Principal component analysis indicated that the variations in characteristics of PNAPMB and MSNAPMB could be explained using total fat, saturated fat, total sugar, ash, moisture, proteins, chroma (C), hue and b*. The results showed that isolated pure cultures could be used as starter cultures in the production of non-alcoholic cereal beverages at a commercial level with predictable quality and safety properties.

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Jalé, João Humberto Pereira da Silva Tavares. "Exploração de recursos vivos marinhos da costa portuguesa. Estudo de caso de pequenos tunídeos: merma ( Euthynnus alletteratus) e judeu (Auxis spp.)". Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5306.

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Mestrado em Engenharia Zootécnica - Produção Animal - Instituto Superior de Agronomia / Faculdade de Medicina Veterinária
The sea related activities always had great importance in Portugal, especially the fishing activity and the processing industry of marine products. However, in the last decades, the decrease of both activities has occurred, with a significant reduction in the number of fishermen and fishing fleet and a major reduction on the number of canning factories in activity, mainly due to the Common Fisheries Politics of EU. In this work, an analysis of the species which make up the food product that retains the case of Auxis spp. (Judeu) and Euthynnus alletteratus (Merma), captured on the Algarve coast and recovered through the process of appertised canning, in nearby Andaluzia, with the designation of "Melva de Andalucía". A sample of 128 individuals was analyzed, in terms of morphometric composition and feeding behavior. The analysis of capture volumes and selling prices variation, in harbor, from 1996 to 2010 was also performed. The assiduous presence of this species was verified, mainly in the summer months, mostly between July and September, when the surface water temperature is higher, although statistically it was not proven, showing similar population composition and feeding and reproductive behavior, in agreement with other authors Works, for the Mediterranean. A sensory evaluation to “Melva de Andalucía” with two other samples of appertised canned products commercialized in Portugal, of similar market segment was performed. The obtained results showed positive answer to the product acceptance by the tasters.

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Wu, Veronica Tong. "Chemical, Physical and Sensory Characteristics of Lactose-reduced Baked Custards Made with a Low-fat, Low-cholesterol Egg Substitute". Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/36644.

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Two experiments were conducted to examine the effects of type of milk (whole; nonfat; nonfat, 70% lactose-reduced) and type of egg (fresh, whole egg; egg substitute) on the quality of baked custards. The egg substitute was a combination of dried egg whit e solids, dried low-fat, low-cholesterol egg yolk solids, and xanthan gum. Custard formulations served as prototypes for use in studies conducted in the Department of Food Science and Technology, Virginia Tech. In those studies, the effects of processing parameters on the quality of the custards were examined. The goal of all the studies was to develop shelf-stable lactose-reduced custard mixes that have potential for use in the foodservice industry.

In Experiment I, chemical, physical, and sensory characteristics of a dessert type baked custard, made with sucrose, were examined. In Experiment II, the same characteristics were examined for a cheese flavored, entree type custard made without sucrose. Results indicate that use of nonfat and nonfat, 70% lactose-reduced milk in place of whole milk decreased significantly total fat and cholesterol concentrations in both types of custard mixes. Lactose-reduced milk also decreased lactose and increased gala ctose concentrations. The egg substitute decreased total fat and cholesterol concentrations and increased protein concentration. In general, lactose reduction had little effect on the physical and sensory characteristics of both types of custards, but the egg substitute affected these characteristics. Custards made with the egg substitute had less intense yellow color and greater gel strength than those made with fresh, whole egg. These custards also were less bright and more uneven in color and had weake r egg flavor and aftertaste.

Based on results of this study, development of a lactose-reduced custard is feasible. However, additional studies are needed to examine potential for use of the formulations in the foodservice industry. Because the mixes could be used as bases for other types of products, such as custard pies, filled pastries, and quiches, studies that focus on development of those products could help define the niche for the mixes in the foodservice industry. Because of the trend in today1s market for reduced-fat, reduc ed-cholesterol foods, additional studies could be done to examine the effects of various types of egg substitutes on the quality of the custards. Master of Science

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36

Hughson, Angus. "Cork and talk the cognitive and perceptual bases of wine expertise /". Connect to full text, 2003. http://hdl.handle.net/2123/490.

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Thesis (Ph. D.)--University of Sydney, 2003.
Title from title screen (viewed Apr. 24, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Psychology, Faculty of Science. Includes bibliography. Also available in print form.

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Bala, Soumya. "Enhancing cysteine content in yogurt with addition of whey protein isolate and its sensory evaluation". Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16270.

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Abstract (sommario):

Master of Science
Department of Food Science
Karen A. Schmidt
Milk proteins are excellent sources of sulfur-containing amino acids methionine and cysteine, in particular whey proteins. Cysteine is synthesized from methionine by γ-cystathionase. However, cysteine has to be included in the diets of certain subpopulations due to diminished γ-cystathionase activity. Cysteine, a heat- liable amino acid, may lose bioavailability during thermal processing. The objective of this research was to enhance cysteine content in yogurt while maintaining its quality. First, yogurt mixes were formulated to a total solids content of 12.5% with nonfat dry milk (NDM) (N) or a combination of NDM (10%) and whey protein isolate (WPI) (2.5%) (W), and processed at 70°C (20 min) (70) or 90°C (7 min) (90). Yogurt was prepared and maintained at 4oC for 60 days. Three replications were performed and data were analyzed using SAS®. The W mixes had 65%, 32% and 190% more cysteine, true protein and whey protein contents respectively, compared to N mixes prior to processing. However in day 1 yogurt, the highest cysteine content (398.3 mg/L) was found in the W70 yogurt and its gel quality was comparable to the N90 yogurt except for firmness. During a 60 day storage period the W70 and N90 were similar in gel quality except for firmness. Secondly, a hedonic test was done on the W70 (HC) and N90 (LC) yogurts which had been reformulated to contain sugar and vanillin. One replication was performed and data were analyzed using SAS®. The LC and HC yogurts did not vary in liking of flavor (6.1), aftertaste (6.1) and overall acceptability (6.3) corresponding to the words of “like slightly” when compared. However, the appearance of the LC yogurt was liked more than the HC yogurt (6.7 vs. 6.1) whereas the thickness of HC yogurt was liked more than the LC yogurt (6.4 vs. 5.8). These results suggest that addition of WPI along with lower process treatment resulted in yogurt with enhanced cysteine; however, further studies may be needed to optimize the WPI addition to improve the visual characteristics of the yogurt for consumer acceptance.

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38

Neto, Luis Gomes de Moura. "Powder mombin (Spondias mombin L.) atomized: Physical, physicochemical and sensory evaluation of the hygroscopic behavior". Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6392.

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Abstract (sommario):

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
The hog plum is a fruit that has good physical-chemical and sensory properties, which give it great acceptance by consumers and industry, and presents excellent nutritional quality. It has sugars, vitamin A and C. In this context, this study aimed to apply the process of atomization in hog plum pulp, using two experimental designs, analyzing the process variables on the yield and quality of the product powder. Following the studies of the powders obtained before their physical characteristics, physical-chemical, hygroscopic, and sensory acceptance of a drink (cajÃ tropical reconstitutedjuice). After acquiring the pulp, it was taken to the laboratory Quality Control and Drying of the DTA / CCA / UFC Fortaleza, where they were stored under refrigeration until the beginning of the process of getting the dust. We used two experimental designs: maltodextrin and / or lecithin as an adjuvant agent. After obtaining parse the parameters of moisture, pH, soluble solids, SS / TA, titratable acidity, total and reducing sugars and colorimetric analysis. Regarding the post, who had maltodextrin and lecithin in the composition stood out from the others in most determinations of physical and physicochemical and sensory attributes, was not only obtained good reputation in the attribute flavor. Among the mathematical models used for the adjustment of adsorption isotherms, the BET model adjusted better to the experimental data of maltodextrin powders with less error and higher correlation coefficient. For the powder with maltodextrin, lecithin, Henderson presented the model is more adjusted, except at a temperature of 40 Â C, than the oneusing the Oswin model. Thus, one can conclude that the application of lecithin in the process of obtaining caja atomized powder is favorable, given the prominence of the post with lecithin in its chemical composition and physical need to study to improve the taste attribute. The spray-dryer process is a good alternative to enjoy the surplus in the production of caja.
O cajÃ Ã um fruto que apresenta boas propriedades fÃsico-quÃmicas e sensoriais, o que lhe conferem Ãtima aceitaÃÃo pelo consumidor e pela indÃstria, alÃm de apresentar excelente qualidade nutricional, contendo aÃÃcares, vitamina A e C. Neste contexto, este trabalho teve como objetivo a aplicaÃÃo do processo de atomizaÃÃo em polpa de cajÃ, por meio de dois delineamentos experimentais, analisando as variÃveis do processo sobre o rendimento e qualidade do produto em pÃ. Seguindo os estudos relativos aos pÃs obtidos diante das suas caracterÃsticas fÃsicas, fÃsico-quÃmicas, higroscÃpicas e, aceitaÃÃo sensorial de uma bebida (suco de cajÃ tropical reconstituÃdo). ApÃs adquirir a polpa, a mesma foi levada ao laboratÃrio de Controle de Qualidade e Secagem do DTA/CCA/UFC em Fortaleza, CE, onde foram armazenadas em refrigeraÃÃo atÃ o inÃcio do processo de obtenÃÃo do pÃ. Foram utilizados dois delineamentos experimentais: a maltodextrina e/ou lecitina como agente adjuvante. ApÃs a obtenÃÃo foi possÃvel analisar os parÃmetros de umidade, pH, sÃlidos solÃveis, SS/AT, acidez titulÃvel, aÃÃcares totais e redutores e anÃlise colorimÃtrica. Em relaÃÃo aos pÃs, os que possuÃam maltodextrina e lecitina em sua composiÃÃo se destacaram dos demais na maioria das determinaÃÃes fÃsicas, e fÃsico-quÃmicas, e dos atributos sensoriais, sÃ nÃo tendo sido obtidos bons conceitos no atributo sabor. Dentre os modelos matemÃticos aplicados para o ajuste das isotermas de adsorÃÃo, o modelo de BET se ajustou melhor aos dados experimentais dos pÃs com maltodextrina com menor erro e maior coeficiente de correlaÃÃo. Para o pÃ com maltodextrina e lecitina, o modelo de Henderson apresentou-se mais ajustado, com exceÃÃo na temperatura de 40ÂC, do que utilizando o modelo de Oswin. Assim, pode-se concluir que a aplicaÃÃo da lecitina no processo de obtenÃÃo de cajÃ em pÃ atomizado Ã favorÃvel, diante do destaque dos pÃs com lecitina em sua composiÃÃo quÃmica e fÃsica, necessitando estudar para melhorar o atributo sabor. O processo de spray-dryer constitui-se de uma boa alternativa para aproveitar o excedente da produÃÃo de cajÃ.

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39

Hsu, Chih-chien, e 徐志杰. "Sensory evaluation of sorghum spirit". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/20553770247011183341.

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Abstract (sommario):

碩士
臺灣大學
食品科技研究所
98
Sorghum spirit is the representative distilled spirit in Oriental society. The objective of this project is to establish the judging procedures of sorghum spirit. Commercial sorghum spirits were analyzed for total acid, volatile acidity, total esters, and fusel oil. The volatile compounds were quantified and qualitative in the commercial sorghum spirits using gas chromatography-mass spectrometry (GC-MS). Six panelists were selected and trained, and those who conducted to characterize sensory attributes of commercial sorghum spirits by descriptive analysis, and established the judging procedures. The descriptive analysis include visual（limpid, suspensions）, nose（complex, balance, intensity, nose tingle, taint）, taste（complex, balance, intensity, nasal effects, taint）. The 18 commercial sorghum spirits were scored by scoresheet of sorghum spirit. Principal component analysis（PCA）indicated that nose-balance（r=0.815）and taste-balance（r=0.899）had the highest positive correlation. The highest positive correlation factor in sorghum spirits is balance by sensory evaluation. Six acids, eleven alcohols, forty esters, eight carbonyl compounds, eighteen miscellaneous were qualitative by GC-MS, and used to explain the description of volatile compounds. PCA indicated that acid had higher negative correlation（r=-0.768）, ester and carbonyl compound had positive correlation（r≧0.568）. There four prime esters in sorghum spirits. Esters were quantified and showed the prime aroma in sorghum spirits. Ethyl caproate were quantified and qualitative in the commercial sorghum spirits using GC-MS. The optimal conditions of solid phase microextraction（SPME）are fiber-DVR/CAR/PDMS（50/30μm）, salt 2％, temperature 40 ℃, absorption time HS-SPME: 60min and DI-SPME:30min, alcohol was diluted by deionized water -HS-SPME :15％(v/v) and DI-SPME:5％(v/v). The sorghum spirit scoresheet indicated that flavor in sorghum spirits and can be used to scored. Keywords: Sorghum spirit, sensory evaluation, solid phase microextraction(SPME), principal component analysis(PCA), gas chromatography-mass spectrophotometer

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40

CHEN, LI-XIN, e 陳立信. "Studies on the tea sensory evaluation". Thesis, 1993. http://ndltd.ncl.edu.tw/handle/54823081459115611926.

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41

Barnes, Debbie L. "Consumer and descriptive panel analysis of commercial yogurts". Thesis, 1990. http://hdl.handle.net/1957/27626.

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A consumer and a trained descriptive panel was utilized to determine liking ratings and flavor profiles, respectively, for commercial brands of pre-stirred yogurt. Once the consumer and descriptive panel data was collected, the data was combined to determine the interrelationship of these two sets of data and to determine the conditions necessary to optimize the sensory characteristics of commercial yogurt. This study was broken down into two parts: (1) evaluation by a 90 to 182 member consumer panel and an 11 member descriptive panel for 14 strawberry and 6 lemon yogurt brands, and (2) correlation of the sensory measures of sweetness and sourness, and analytical measures of sugars and acids for 14 strawberry, 12 raspberry, 6 lemon, and 17 plain yogurt brands. Large sensory differences were found between yogurts for both flavors (strawberry and lemon) by both panels. Correlation and principal component analysis (PCA) indicated that two distinct groups of descriptors contributed to the liking of the yogurts: one associated with the fruity and sweetness characteristics, and the other related to the plain yogurt and sourness descriptors. Consumers based their overall liking ratings on fruit flavor, sweetness, sourness, and a balance of sweetness/sourness liking. Males and females rated samples differently by as much as one full scale value on a 9-pt. hedonic scale. Use of PCA to relate the two panels revealed that high consumer acceptance corresponded with the PC loaded with fruity and sweet characteristics while lower consumer acceptability was noted with high loadings on PC2 which was comprised of plain yogurt, acetaldehyde, and sourness descriptors. The results from the first part of the study indicate that to produce a highly acceptable yogurt, processors should strive to provide a balance between sweetness and sourness and provide enough fruit flavor to mask plain yogurt characteristics. In the second part of this study, titratable acidity and pH were measured for all the yogurts, while sugars were measured by HPLC only for the fruit flavored yogurts. Consumer overall liking was significantly correlated with sweetness intensity, sweetness:sourness (sw:so) ratio, and the summed impact of sweetness and sourness from the trained panel for strawberry and raspberry yogurt. No correlations between analytical measures and overall liking were found for any of the yogurts. A sw:so ratio greater than 1.0 for strawberry, and .8 for raspberry and lemon appeared necessary for high consumer acceptance. Generally, it was found that the sweeter the yogurt, the higher the consumer acceptance of fruit flavored yogurt. No relationships were found for any sensory and analytical measures for predicting the overall liking of plain yogurt. However, the best predictors of consumer liking of fruit flavored yogurt were the descriptive panel ratings.
Graduation date: 1991

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42

Mokwena, Moshadiwa Germina. "The effect of pale, soft and exudative (PSE) pork on the sensory quality characteristics of low fat bacon". Diss., 2003. http://hdl.handle.net/2263/26904.

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This research focused on studying the sensory quality of low fat bacon when pale, soft and exudative (PSE) pork is used during processing. Low fat bacon is different from normal bacon in that the amount of visible fat in low fat bacon has been reduced. This is as a result of consumer interest in weight control and cholesterol, creating a demand for meat and meat products with reduced fat levels. PSE pork is a condition in which certain muscles are very pale, soft and watery. It is produced when the rate of post-mortem glycolysis is fast and a high level of acidity is reached while the carcass temperature is still high. Different researchers have reported that PSE pork absorbs less brine during curing and this may have a negative effect on the sensory quality and acceptance of both the uncooked and cooked finished products as it is mainly the curing brine that is responsible for the development of the typical colour, flavour, aroma and texture associated with cured meat products. Thirty pig carcasses, 15 PSE and 15 normal pH, suitable for production of low fat bacon, were selected over a period of three weeks at an abattoir in Olifantsfontein to study the effect of PSE meat on the sensory quality of low fat bacon. The carcasses were further processed into low fat bacon at a meat processing plant. Data were collected on the % brine uptake of PSE and normal pH meat after curing; the rating scores on the descriptive sensory attributes of both PSE and normal pH low fat bacon and the % salt concentration and residual nitrite of PSE and normal pH low fat bacon. A consumer test to determine the buying preferences for packaged PSE and normal pH low fat bacon and the eating quality preferences of cooked PSE and normal pH low fat bacon was also conducted. No significant difference (p > 0.05) was found in the % brine uptake between PSE and normal pH meat. There were no significant differences (p > 0.05) in the descriptive sensory attributes of PSE and normal pH low fat bacon. The residual nitrite concentration of normal pH low fat bacon was significantly higher than that of PSE low fat bacon. There was however no significant difference (p > 0.05) in the % salt concentration of PSE and normal pH low fat bacon. Correlation matrices showed significant positive correlations (p ≤ 0.05) between % brine uptake and % salt concentration and between % salt concentration and perceived saltiness of normal pH low fat bacon. For PSE low fat bacon, the correlations between % brine uptake and % salt concentration and between % salt concentration and perceived saltiness was not significant. The correlation between % brine uptake and residual nitrite content was however not significant (p > 0.05) for both the PSE and normal pH low fat bacon. A significantly higher number of consumers indicated that they would prefer to buy samples representing PSE low fat bacon. The pale colour of PSE meat was not masked after curing, which was noticed by the consumers during the evaluation of buying preferences for PSE and normal pH packaged low fat bacon. However, regarded as even more important than colour, the consumers mentioned fat content as the main deciding factor for purchasing low fat bacon. No significant difference (p > 0.05) was found in the preference for the eating quality of cooked PSE and normal pH low fat bacon. It was concluded that PSE meat can successfully be used to produce low fat bacon products of consistent quality. This conclusion is drawn from the analytical sensory test results, where the use of PSE meat did not affect the sensory quality characteristics of low fat bacon. For low fat bacon, fat content is an important factor, regarded as very influential to consumers when making purchases. It is therefore important to produce products with consistent fat content according to specifications.
Dissertation (M Inst Agrar ( Food Production and Processing))--University of Pretoria, 2005.
Food Science
unrestricted

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43

Wong, Hiu Yu. "The effect of pale, soft and exudative (PSE) pork and fat grading on physico-chemical characteristics of low fat bacon". Diss., 2003. http://hdl.handle.net/2263/26905.

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44

Sanchez, Nora B. "Analytical and sensory evaluation of hop varieties". Thesis, 1990. http://hdl.handle.net/1957/27074.

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Abstract (sommario):

The German hop Hallertauer, hallertauer is highly valued because of its "noble aroma", but it has a very low yield when cultivated in the U.S. Two new crosses of Hallertauer, U.S.D.A. 21455 and 21459, have high yields and promising aroma characteristics. In order to predict sensory properties of beers as a function of the varieties of hop used in brewing, a more complete sensory and chemical characterization of hop oils is necessary. The aims of this study were to compare the aroma profiles of the new crosses against the German variety by determining their most important odor active compounds, and correlating the sensory attributes evaluated by a descriptive sensory panel (DSP) with the odor intensities detected during the gas chromatograph (GC) effluent detected during the gas chromatograph (GC) effluent sniffing. Oxygenated fractions were spiked into spring water and evaluated by the DSP. The same samples were injected into the GC and the effluents were evaluated quantitatively and qualitatively by four subjects using a special data collection device. Samples were then analyzed by mass spectrometry (MS). There were no significant differences among the three varieties based upon the DSP results and the "aromagrams" obtained during the sniffing of the GC effluents. Important odor active peaks were associated with humulene oxidation products. A number of statistical correlations existed between the sensory attributes and the odor active peaks. In summary, the new varieties are potential contributors to "noble aroma". Trials with beers brewed with these hops are underway in order to establish their contribution to beer flavor.
Graduation date: 1990

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45

Sims, Tiffany. "Evaluation of postural stability using sensory organization test". Thesis, 2004. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2004-015.

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46

Wiseman, Jennifer Jo. "The effect of sucrose, aspartame, acesulfame-K and blended aspartame/acesulfame-K on orange and strawberry flavor in model solutions". Thesis, 1991. http://hdl.handle.net/1957/27063.

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Abstract (sommario):

The effect of sweeteners on fruit flavor perception was studied through the use of fruitiness power functions for unsweetened and sweetened model systems. In the first part of the study, two isosweet concentrations of aspartame and sucrose were determined and combined with five concentrations of orange and strawberry flavorants. Fruitiness power functions were developed and compared to determine the effect of each sweetener on the fruit flavor. For the second part of the study in the first experiment, one isosweet concentration of sucrose, aspartame, acesulfame-K and 1:1 blended APM/Ace-K was combined with five concentrations of each of three orange flavorants. Fruitiness power functions were developed and compared to determine how each sweetener effected the fruit flavor of each flavorant. The second experiment addressed the question of whether or not subjects associated sweet taste with fruitiness or if there was an actual change in the volatile composition of the aroma between the unsweetened reference and the sweetened solutions. Fruit aroma of the middle concentration of each flavorant sweetened with the four sweeteners was compared to the corresponding unsweetened reference. Enhancement of fruitiness was observed in the aspartame sweetened systems at low flavor levels. The power function slopes of both flavorants were lowered by the addition of aspartame which resulted in a slower rate of growth in fruitiness perception with the addition of flavorant to the system. In both the orange and strawberry flavored systems the aspartame sweetened solutions were rated higher in fruitiness than the sucrose sweetened solutions. The enhancement was more pronounced in the orange flavored system, suggesting a flavorant effect. The sweeteners affected the fruitiness perception of the three orange flavorants in different magnitudes but the patterns were similar. The three fruitiness slopes were all lowered by the addition of each sweetener. Flavor enhancement was greatest in flavor 1 sweetened with aspartame or aspartame/acesulfame-K. The higher relative placement and low slope of the fruitiness power functions in aspartame sweetened systems caused the enhancement effect to be greatest over the lower concentrations of each flavorant. In the second experiment, the fruit aroma of aspartame sweetened solutions in flavor 1 was significantly higher than the other sweetened solutions. The fruit aroma of the second and third flavorants was not significantly changed by the sweeteners.
Graduation date: 1992

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47

Savant, Lotika. "Suppression of sourness in binary and tertiary model mixture solutions". Thesis, 2001. http://hdl.handle.net/1957/25906.

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Abstract (sommario):

Addition of acids to foods allows for enhanced food safety. Acids are the primary form of defense against microbial contamination in refrigerated foods, while use of acids in conjunction with heat or high hydrostatic pressure processing lowers energy usage resulting in cost reduction. However, addition of acids to food or beverage formulations often reduces palatability due to higher sourness and this has limited the food industry's ability to better utilize them as preservatives. This study was aimed at gaining a better understanding of sourness suppression and its underlying mechanisms so that such limitations might be ultimately overcome. This work was divided into three parts dealing with the suppression of the sourness of citric, lactic and malic acids, as perceived by a trained sensory panel in a) binary mixtures with sugars, b) binary mixtures with salts and c) tertiary mixtures. The results of the first part showed that suppression was not mediated by sugar molarity or weight, but was significantly influenced by its perceived sweetness intensity in most cases. Sucrose and fructose were more effective than glucose in suppressing acid sourness and the data supported a separate receptor site/mechanism for glucose. Suppression was thought to have both central and peripheral components. In binary acid-salt mixtures sodium acetate (NaAc) affected the most sourness reduction, along with the largest concurrent pH increase (above 4.4). Sodium chloride (NaCl) mixtures showed significant suppression without a pH increase. Sodium gluconate (NaGluc) mixtures showed moderate suppression with citric and malic acids with pH increases remaining below 4.4, but showed little effect on lactic acid sourness. Saltiness appeared to drive suppression only in the case of NaCl, while pH change was responsible for reduction of sourness with NaAc and NaGluc. The tertiary trials indicated that a two-component multiple masker was more effective when its components stimulated different (as opposed to similar) receptors/receptor mechanisms in the taste system, irrespective of taste quality. Furthermore, a two-component masker was more effective than each component alone, and both components of a two-component masker did not have to be effective individually for them to function together as an effective multiple masker.
Graduation date: 2002

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48

Janto, Mimi. "Quality assessment of Asian noodles made from U.S. wheat flours using sensory descriptive analysis". Thesis, 1997. http://hdl.handle.net/1957/27243.

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Abstract (sommario):

As a major wheat exporter to countries all over the world, the United States has to produce wheat that satisfy different quality requirements requested by their customers. Over the past decade the United States has encountered a major problem, that of losing market share in Asia to Canada and Australia. The major reason was that the United States was unable to supply Asian countries with quality wheat suitable for noodle production. To overcome the problem, the U.S. wheat industry needs to understand the specific quality requirements required for Asian noodles. Research on understanding sensory characteristics of Asian noodles was proposed to bridge the communication barrier regarding Asian noodle quality. Descriptive analysis was utilized for this study to provide sensory characteristics of noodles from different Asian countries. In the first study, four classes of U.S. wheat flour samples were evaluated for their ability to make high quality Taiwanese noodles. Taiwanese noodle industry representatives came to the United States and made 4 major types of their noodles using U.S. wheat flours; they evaluated them by employing both the Taiwanese industries' scoring system and modified descriptive analysis. The results of this study indicated that hard white wheat was suitable for making two types of Taiwanese noodles (dry and yee noodles), a blend of hard red winter and hard red spring wheat was suitable for wet noodles, and a blend of hard red winter and white wheat was suitable for fresh noodles. The second study was undertaken to better understand the texture profile of noodles from various Asian countries. Sensory texture characteristics of fresh noodles from Taiwan, Thailand, and Malaysia were identified. A total of 16 patent flour samples for Taiwan, and 18 straight grade flour samples each for Thailand and Malaysia, were milled from hard white wheat varieties and made into each Asian country's noodles. A texture profile of each country's noodles was developed by an Oregon State University descriptive panel while quality evaluation was performed by each countries' noodle experts. The results characterized the Taiwanese noodles as the smoothest, springiest, and highest in integrity of noodles; the Thai noodles were the hardest, most dense, cohesive noodles and also higher in starch between teeth and toothpull; and the Malaysian noodles were the softest, least dense, cohesive, and sticky noodles. The optimum protein to achieve specific texture quality for each country was identified.
Graduation date: 1998

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49

Briggs, Judith A. "Sensory evaluation and shelf-life modeling of ground coffee". Thesis, 1999. http://hdl.handle.net/1957/27777.

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Both consumer and descriptive analyses were used to study the shelf-life of packaged, roasted and ground coffee in order to evaluate the utility of using sensory data in a shelf life model, and to examine the ability of consumers to detect a difference between treated and control samples. Two types of coffee, which differed in bean roast, blend and origin, were evaluated and were referred to as moderate roast and high roast. Samples were packaged under <2%, 9%, or 21% oxygen in airtight laminated foil packages. Over the course of 84 days, the samples were stored in 20��C, 30��C, or 40��C conditions and samples for all treatments were removed throughout the storage. The control samples were packaged at <2% oxygen and stored at -35��C for the duration of the study. Descriptive results illustrated a time trend in the moderate roast coffee along Factor 1, characterized by changes in the attributes of paper aroma, paper flavor, paper aftertaste, wood flavor, body, and oily mouthfeel. This trend resulted in significant differences between the control and the 40��C high oxygen 7 day stored samples in paper aroma (p=0.000) and paper flavor (p=0.000), as well as significant differences between the control and the 40��C high oxygen 49 day stored samples in paper aroma (p=0.002), paper flavor (p=0.000), paper aftertaste (p=0.000), body (p=0.000), and wood flavor (p=0.002). Factor I data from the 40��C high oxygen, moderate roast coffee were utilized in an Arrhenius shelf-life model. A second order model was fit to the data, indicating curvature in relationship for the rate of change over temperature for Factor 1 attributes. The model successfully generated a predictive curve for storage at 40��C. Consumers evaluated 30��C stored samples packaged under high oxygen and stored for either 4 or 7 days, and packaged under low oxygen and stored for 42 and 84 days. Consumer results indicated that it was difficult for consumers to detect differences between the moderate roast coffees. Consumers were readily able to tell significant differences between the high roast coffee treatments and the control sample (p<0.05).
Graduation date: 2000

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Yu, Chain-Li, e 余佳俐. "Sensory evaluation and chemical constituents in Taiwan oolong teas". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/78347862420398392729.

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碩士
國立中興大學
食品暨應用生物科技學系所
100
Tea is grown in more than thirty countries worldwide that is originated in South East Asia. The quality and the commercial value of tea are closely related to human sensory evaluation of tea infusion which includes, leaf appearance, color, aroma, taste, and mouthfeel of the tea infusion. The aroma and taste of tea infusion are the most important attributes among these indicators. Whether these indices are directly related to chemical constitutes remains to be established. The composition and sensory evaluation of tea can also be affected by geographical location, cultivar species, season of harvest, and the age of the leaves. The aim of this study was to characterize popular Taiwanese teas including Chin-Shin-Oolong, Chin-Shin-Dapan, Tie-Kuan Yin, Shy-Jih Chue, Jin-Xuan, Tsue-Yu. Tea samples harvested in different seasons or collected from different areas with different altitudes were collected and compared. The sensory evaluation of tea samples was performed by a panel of certified experts from the Tea Research and Extension Station (TRES) in Taiwan. The chemical constituents of various tea infusions were analyzed by Gas chromatography/mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). The association between the sensory scores, the altitude and season of different teas were also investigated.

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