Academic literature on the topic 'Fruit acidity'
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Journal articles on the topic "Fruit acidity"
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Jiang, Yonghua, Yingwei Qi, Xilong Chen, Qian Yan, Jiezhen Chen, Hailun Liu, Fachao Shi, Yingjie Wen, Changhe Cai, and Liangxi Ou. "Combined Metabolome and Transcriptome Analyses Unveil the Molecular Mechanisms of Fruit Acidity Variation in Litchi (Litchi chinensis Sonn.)." International Journal of Molecular Sciences 24, no. 3 (January 18, 2023): 1871. http://dx.doi.org/10.3390/ijms24031871.
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Fruit acidity determines the organoleptic quality and nutritive value of most fruits. In litchi, although the organic acid composition of pulps is known, the molecular mechanisms and genes underlying variation in fruit acidity remain elusive. Herein, developing pulps of two contrasting litchi varieties, Huaizhi (HZ, low-acidity) and Boye_No.8 (B8, high-acidity), were subjected to metabolomics and transcriptomics, and the dynamic metabolome and transcriptional changes were determined. Measurements revealed that the dominant acidity-related organic acid in litchi pulps is malate, followed in low levels by citrate and tartrate. Variation in litchi pulps’ acidity is mainly associated with significant differences in malate and citrate metabolisms during fruit development. Malic acid content decreased by 91.43% and 72.28% during fruit ripening in HZ and B8, respectively. The content of citric acid increased significantly in B8, while in HZ it was reduced considerably. Differentially accumulated metabolites and differentially expressed genes analyses unveiled fumarate, succinate, 2-oxoglutarate, GABA (γ-aminobutyric acid), phosphoenolpyruvate, and citrate metabolisms as the key driving pathways of litchi fruits’ acidity variation. The drastic malate and citrate degradation in HZ was linked to higher induction of fumarate and GABA biosynthesis, respectively. Thirty candidate genes, including three key genes (LITCHI026501.m2, fumarase; LITCHI020148.m5, glutamate decarboxylase; and LITCHI003343.m3, glutamate dehydrogenase), were identified for functional studies toward genetic modulation of litchi fruit acidity. Our findings provide insights into the molecular basis of acidity variation in litchi and provide valuable resources for fruit quality improvement.
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D’ABADIA, ANA CLAUDIA ALVES, ANA MARIA COSTA, FÁBIO GELAPE FALEIRO, MARIA MADALENA RINALDI, LÍVIA DE LACERDA DE OLIVEIRA, and JUACI VITÓRIA MALAQUIAS. "DETERMINATION OF THE MATURATION STAGE AND CHARACTERISTICS OF THE FRUITS OF TWO POPULATIONS OF Passiflora cincinnata Mast." Revista Caatinga 33, no. 2 (April 2020): 349–60. http://dx.doi.org/10.1590/1983-21252020v33n208rc.
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ABSTRACT Passiflora cincinnata Mast. (caatinga passion fruit) has acidic fruits with a peculiar flavor, green color when ripe and a low percentage of abscission making it difficult to identify the point of harvest. In order to verify the harvest period in two populations of P.cincinnata, flowers were marked in anthesis and after six periods the fruits were harvested. This study evaluated fruit mass, seeds and pulp mass, fruit dimensions and shape, percentage of water, color and texture of skin, volume, color and pulp yield, pH, soluble solids (SS), titratable acidity ratio, polyphenol content, flavonoids and anthocyanins. The assay was designed in a completely randomized design in a factorial arrangement (2x6), with two populations (CPEF2220 and CBAF2334) and six harvest periods (20, 40, 60, 80, 100 and 120 days after anthesis - DAA) with four repetitions. There was a reduction in thickness (43.1%) and percentage of water in the skin (9.3%), pH (40.1%), ratio, polyphenols content and pulp luminosity (brightness). There were increases in pulp mass and volume, seed mass, pulp mass yield in relation to the fruit (72%), and SS titratable acidity (44.9%) in CPEF2220 and equality between populations in fruit shape, pulp color, thickness and skin color (luminosity and ºhue), pH and polyphenols. Although after 100 DAA there were higher yields, between 60 and 80 DAA it was possible to identify characteristics of SS, pH, titratable acidity, mass, volume and pulp yield related to ripe fruits, allowing harvesting after 60 DAA.
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Sallin, Valéria Pancieri, Douglas Vicente do Carmo Lima, Maria Juliete Lucindo Rodrigues, Matheus Torezani Rossi, Vinicius De Souza Oliveira, and Edilson Romais Schmildt. "Classification to Coefficient of Variation in Physical and Chemical Attributes of Oranges." Brazilian Journal of Experimental Design, Data Analysis and Inferential Statistics 2, no. 2 (November 23, 2022): 12–18. http://dx.doi.org/10.55747/bjedis.v2i2.52551.
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Abstract: A of the ways to evaluate data homogeneity in experiments is through the coefficient of variation (CV), however, in orange fruit evaluations, gaps are noted about the ranges that the variables must present due to their fluctuations as a function of factors genetic, climatic and agricultural. Thus, the present work aims to propose classifications of coefficient of variation for physicochemical attributes of orange fruits. For this purpose, CVs of 42 articles were used, considering soluble solids (SS), titratable acidity (TA), soluble solids and titratable acidity ratio (SS/TA), fruit length (FL), fruit diameter (FD), fruit mass (FM) and juice yield (JY), applying descriptive statistics and the Shapiro Wilk normality test. The limits proposed as low CV for the physical-chemical attributes of total soluble solids, titratable acidity, the ratio of total soluble solids and titratable acidity, fruit length, fruit diameter, fruit mass, and juice yield are respectively 2.11; 4.39; 4.46; 2.27; 2.59; 4.71 and 1.99% while the high CV range corresponds in the same sequence to 9.61;15.02;15.12;8.99;9.69;19.39;16.34%.
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Azher, Umme, Vijayashree C, Santhosh T Paul, and Divya C Reddy. "Assessment of the Erosive Potential of the Commonly Consumed Fruit-Based Beverages Among Children." RGUHS Journal of Dental Sciences 13, no. 4 (2021): 253–57. http://dx.doi.org/10.26715/rjds.13_4_7.
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Background: Dental erosion, an irreversible loss of dental hard tissue by a chemical process without the involvement of bacteria can be caused by various intrinsic and extrinsic factors. The consumption of foods with a low pH can cause a drop in the pH of the oral cavity below critical pH and its persistence can lead to a potential damage to teeth. As acidic beverages are likely to be a major factor in the etiology of dental erosion, it is important to determine the erosive potential of commonly consumed fruit-based beverages among children and educate the parents of their detrimental effects on teeth. Objectives: To evaluate and compare the pH and titratable acidity of the commonly consumed fruit-based beverages. Methodology: Three commonly consumed flavours (Orange, Apple, Mixed fruit) of fruit-based beverages (Group 1 - fresh fruit juice; Group 2 - packed fruit juice; Group 3 - packed fruit drink) were analyzed for pH and titratable acidity. The pH was determined using digital pH meter and the titratable acidity was measured by adding 1M sodium hydroxide (NaOH) in increments of 0.2 ml to 100 ml of the freshly prepared/ opened fruit-based beverages until the pH reached 5.5 and 7. The pH reading was measured after each increment (0.2 ml) of NaOH, until a stable pH was achieved. All the measurements were repeated in triplicates. Results: The pH of all drinks investigated in the present study ranged between 3.29 - 4.43. On comparison of the titratable acidity, packed fruit drink (Group 3) exhibited highest titratable acidity, followed by packed fruit juices (Group 2) and fresh fruit juices (Group 1). Conclusion: All the fruit-based beverages in the present study exhibited an acidic pH, which was well below the critical pH of 5.5, thereby exhibiting an erosive potential.
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VIANA, ELISETH DE SOUZA, FABIANA FUMI CERQUEIRA SASAKI, RONIELLI CARDOSO REIS, DAVI THEODORO JUNGHANS, IOHANA SCARLET ALMEIDA GUEDES, and ELAINE GOES SOUZA. "QUALITY OF FUSARIOSIS-RESISTANT PINEAPPLE FRF 632, HARVESTED AT DIFFERENT MATURITY STAGES." Revista Caatinga 33, no. 2 (April 2020): 541–49. http://dx.doi.org/10.1590/1983-21252020v33n226rc.
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ABSTRACT The objective of this study was to evaluate the influence of the harvest maturity stages on the physical, chemical and sensorial quality of the pineapple genotype FRF 632. The fruits were harvested in the maturity stages “green-ripe”, “spotted”, “colored” and “yellow” and evaluated regarding fruit and flesh mass; flesh yield; fruit and crown length; diameter of the basal, middle and top fruit sections; flesh color; titratable acididy (TA); translucency; soluble solids (SS); SS/TA ratio; and sensory acceptance of the attributes color, aroma, flavor, texture/firmness, overall acceptance and intensities of the attributes sweetness, acidity and firmness, using the just about right scale. There was no difference for the majority of the physical traits of the fruits at the various harvest maturity stages. The fruits had average mass of about 1,100 g. There was a gradual increase in the content of soluble solids and the SS/TA ratio during ripening. The fruits collected at the “colored” and “yellow” stages had the highest approval percentages and were considered to have ideal sweetness and acidity by the majority of consumers in sensorial tests. However, the preference mapping revealed a greater preference for fruits harvested in the “spotted” and “colored” stages for all the attributes assessed, unlike what was observed in the test of average and approval percentage. Therefore, the physical, chemical and sensorial tests indicate that the fruits harvested in the “colored” maturity stage were most preferred by consumers, since they had high approval percentage, as well as ideal sweetness and acidity.
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Milošević, T., N. Milošević, I. Glišić, and G. Šekularac. "Influence of stock on physical and chemical traits of fresh apricot fruit." International Agrophysics 27, no. 1 (January 1, 2013): 111–14. http://dx.doi.org/10.2478/v10247-012-0075-x.
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Abstract The study was conducted to determine the effects of Myrobalan rootstock and Blackthorn interstock on fruit physical and chemical traits of five apricot cultivars. The results showed that cultivars grafted on Myrobalan rootstock appear to induce a higher fruit mass when compared with the Blackthorn interstock. Blackthorn interstock showed a tendency to induce a higher soluble solids/titratable acidity ratio than Myrobalan. Values of soluble solids content, total sugars, titratable acidity and fruit firmness between Myrobalan rootstock and Blackthorn interstock were not significant. Regarding cultivars, the greatest fruit mass observed in Roxana in both treatments, and the lowest in Biljana on Myrobalan and in Vera on Blackthorn. The lowest soluble solids, total sugars and soluble solids/titratable acidity ratio were found in Roxana in both variants of grafting, whereas the greatest titratable acidity also observed in Roxana in both cases, respectively. Based on the results from this study, the fruits of Roxana can be recommended for fresh consumption, whereas fruits of the other cultivars can be recommended for processing.
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SAINI, ANIL KUMAR, SUSHIL KUMAR SHARMA, ANIL KUMAR, PANKAJ KUMAR, and DHARMENDAR SINGH. "Analysis of biochemical basis of resistance mechanism of aonla (Emblica officinalis) varieties against blue mould rot disease (Penicillium islandicum)." Indian Journal of Agricultural Sciences 88, no. 11 (November 16, 2018): 1770–78. http://dx.doi.org/10.56093/ijas.v88i11.84929.
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Experiment was carried out at Chaudhary Charan Singh Haryana Agricultural University, Hisar to understand biochemical basis of resistance under in vitro conditions in aonla (Emblica officinalis Gaertn.). In biochemical basis of resistance, it was observed that TSS (total soluble solids), total phenol, peroxidase (PO) and polyphenol oxidase activity (PPO) was higher in diseased fruits in comparison to healthy fruits. TSS and total phenol increased in healthy and diseased fruits over time interval (5 and 10 days after inoculation). The titrable acidity was significantly lower in susceptible varieties, viz. Chakaiya (healthy fruit, 1.22 % and diseased fruit, 0.98 %) and Banarasi (healthy fruit, 1.40 % and diseased fruit, 1.32 %) as compared to resistant varieties Desi (healthy fruit, 1.50 % and diseased fruit, 1.42 %) and Kanchan (healthy fruit, 1.52 % and diseased fruit, 1.51 %). Ascorbic acid in resistant varieties Desi and Kanchan was 482.03 and 500.93 mg/100 g m aonla pulp in healthy fruits while 465.59 and 476.18 mg/100 g aonla pulp in diseased fruits after 10 days of storage. PO and PPO was found to be significantly higher in diseased fruits of resistant varieties, i.e. Desi (145, 20.49 OD/min/g) and Kanchan (139, 19.50 OD min/g) as compared to diseased fruits of susceptible Chakaiya (120, 16.19 OD/min/g) and Banarasi (118, 15.14 OD/min/g) at 5 DAI. However, the activity of PO and PPO decreased after 5 days of inoculation, while acidity and ascorbic acid was low in diseased fruits when compared to healthy fruits and further decreased over time interval. Ascorbic acid and acidity was decreased over time in both healthy and diseased fruits but at faster rate in diseased fruits as compared to healthy fruits.
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Arenas, Marian Guadalupe Hernández, Daniel Nieto Angel, María Teresa Martínez Damian, Daniel Teliz Ortiz, Cristian Nava Díaz, and Nestor Bautista Martinez. "Characterization of rambutan (Nephelium lappaceum) fruits from outstanding mexican selections." Revista Brasileira de Fruticultura 32, no. 4 (January 7, 2011): 1098–104. http://dx.doi.org/10.1590/s0100-29452011005000004.
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Fruits of five regional selections of rambutan (Nephelium lappaceum L.) were characterized to identify those with international marketing quality to promote their propagation in Mexico, improvement and conservation in germoplasm bank. The fruits were harvested in June, July, and August 2008 and, after each harvest, were assessed for shape (length/diameter), firmness, fruit weight, number of fruits per kilogram, weight and percentage of pericarp, seed and aril, total soluble solids, total sugars, vitamin C content, pH, and titratable acidity. In addition, a sensorial evaluation was carried out with 31 panelists who graded each selection for color, sweetness, and acidity. Fruits of five selections were ovoid, and with the following characteristics: firmness values from 43.7 to 51.0 N, fruit weight ranged from 22.4 to 34.7 g, registering from 28.9 to 45.0 fruits per kg; pericarp weight from 10.5 to 17.3 g (45.9 to 49.9% of the total fruit weight); total seed weight from 2.2 to 2.5 g (7.0 to 10.0%); average arils weight from 8.9 to 13.1 g (37.5 to 41.4%). The fruits had high contents of total soluble solids (17.8 to 20.4 ºBrix), total sugars (211.95 to 242.70 mg/100g in the edible portion), vitamin C (37.9 to 69.1 mg/100 g), pH 5.0, and titratable acidity of 0.20 to 0.28%. The fruits from the RT-01 and RT-05 selections had better attributes in fruit weight, total soluble solids and titratable acidity and were better accepted by the panelists. Harvest date significantly affects rambutan fruit quality; at the middle and end of the season harvested fruits had better qualitative characteristics for the marketing.
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Breemer, Rachel, Syane Palijama, and Febry R. Palijama. "Pengaruh Pengaturan Suhu Penggorengan Vacum Terhadap Sifat-Sifat Kimia Keripik Salak (Salaca edulis Reinw)." AGRITEKNO, Jurnal Teknologi Pertanian 7, no. 2 (October 1, 2018): 56–59. http://dx.doi.org/10.30598/jagritekno.2018.7.2.56.
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Snake fruit (Salaca edulis Reinw) has a taste of sweet and sour, with a strong astringent edge. Snake fruit can be processed into chips in order to prolong its shelf life. Fruit chips processed with vacuum frying technology does not compromise the form, taste, colour, and aroma of the native fruits. However, in an effort to obtain crisp and tasteful snake fruit chips, the temperature of the vacuum frying process should be adjusted accordingly. Results showed the frying temperature of 70°C resulted in the chips which had Vitamin C, total acidity, and moisture contents of 0.11 mg, 16.05%, and 12.74%, respectively. When chips were fried with 80°C, the resulting product had a Vitamin C of 0.12 mg, total acidity of 16.14%, and moisture of 14.02%. Whereas chips with lower Vitamin C, total acidity, and moisture contents of 0.09 mg, 8,54%, and 6.01%, subsequently resulted from frying with 90°C.
Keywords: chips, snake fruits, vacuum frying
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Souza, J. L. C., L. B. Silva, R. X. Costa, and M. C. Vieira. "Physical and chemical characterization of mama-cadela and araçá fruits collected in the cerrado of Goiás." Scientific Electronic Archives 13, no. 7 (July 1, 2020): 39. http://dx.doi.org/10.36560/13720201006.
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The objective of this work was to evaluate the physical and chemical characteristics of fruits of different matrices of mama-cadela and araçá. Physical evaluations were: longitudinal fruit diameter (DLF), fruit cross diameter (DTF), fruit mass (MF), longitudinal seed diameter (DLS), seed transverse diameter (DTS) and seed mass (MS) . Chemical analyzes consisted of analyzing pH, titratable acidity, humidity and ashes. The results of the physical and chemical analyzes were subjected to analysis of variance (ANOVA) and the Scoott-Knott test (p <0.05). The mean values of DLF; DTF; MF; DLS; DTS; MS; pH; titratable acidity; moisture and ash of the bitch-breast fruits were: 2.18 cm; 1.95 cm; 4.34 g; 1.73 cm; 1.40 cm; 1.57 g; 4.97; 0.49%; 66.31% and 32.50%. The fruits of araçá presented average values of longitudinal, transverse diameter, fruit mass, pH and titratable acidity: 2.58 cm; 2.03 cm; 6.39 g; 3.44; and 0.94%. The results showed variability among the mama-cadela breeds regarding chemical and physical evaluations; and no differences were observed between the araçá matrices in the physical variables..
Dissertations / Theses on the topic "Fruit acidity"
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Petje, Kgomoamogodi Felix. "Determination of fruit yield and fruit quality in marula (Sclerocarya birrea subsp. caffra) selections." Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-08072009-130342.
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Etienne, Audrey. "Quels processus physiologiques pilotent l’acidité de la banane dessert (sp. Musa) en pré et post récolte ? : Modélisation écophysiologique et analyse expérimentale de l’effet du génotype et des conditions de croissance du fruit." Thesis, Antilles-Guyane, 2014. http://www.theses.fr/2014AGUY0777/document.
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Chez la banane dessert, les saveurs sucrée et acide, caractéristiques importantes pour les consommateurs, sont pilotées par les teneurs en acides citrique et malique. Ce travail a donc porté sur l’étude des processus physiologiques qui pilotent l’accumulation de ces acides dans la pulpe de banane (Musa sp. AA) en combinant analyse expérimentale et modélisation écophysiologique. Nous nous sommes notamment intéressés à l’effet du génotype et des conditions de croissance du fruit en adoptant une approche intégrative liant les phases pré et post récolte.Les effets de la charge en fruit, de la fertilisation potassique, et du stade de récolte sur l’accumulation du citrate et du malate dans la pulpe ont été étudiés expérimentalement. La variabilité génotypique a été prise en compte en choisissant trois génotypes présentant des acidités contrastées à maturité. Des différences d’évolution des teneurs en acides, dues à des modifications métaboliques, ont été observées entre les génotypes pendant les phases pré et post récolte. Le stade de récolte a eu un effet significatif sur les teneurs en acides des fruits pendant la maturation post récolte. La charge en fruit et la fertilisation potassique n’en ont eu aucun. Des modèles écophysiologiques ont été développés pour prédire différents critères d’acidité de la banane en pré et post récolte. Le pH et l’acidité titrable ont été prédits par un modèle d’équilibres acido-basiques, la teneur en malate par un modèle de stockage vacuolaire, et la teneur en citrate par un modèle du cycle de Krebs. Ces modèles ont permis d’identifier les processus physiologiques clés qui pilotent l’acidité de la banane. Des paramètres génotypiques ont été identifiés liés à l’activité de l’enzyme malique mitochondriale et à celle des transporteurs mitochondriaux du malate pour le modèle citrate, et à l’activité des pompes à protons vacuolaire ATPases pour le modèle malate. Ces modèles ont également permis de disséquer l’effet des conditions de croissance du fruit sur l’acidité de la banane. L’intégration des modèles développés dans un modèle d’élaboration de l’acidité et son utilisation potentielle pour l’amélioration variétale sont discutéesCitric and malic acids determine the sourness and sweetness of banana pulp, which are the two main determinants of consumer preferences. The present work focused on the physiological processes controlling the accumulation of citric and malic acids in banana pulp (Musa sp. AA) using experimental analysis and ecophysiological modeling. We chose an integrative approach linking the pre and post-harvest stages, and focused on the effect of genotype and fruit growing conditions. Experiments were conducted to study the effect of fruit load, potassium fertilization and fruit age at harvest on the accumulation of citrate and malate in banana pulp. To account for genotypic variability, three genotypes with contrasting acidity at the eating stage were studied. Major differences in the pattern of citrate and malate accumulation were found in the three cultivars both during growth and post-harvest ripening and were shown to be the result of metabolic changes. The harvest stage had a significant effect on the concentrations of acids during post-harvest ripening. Fruit load and potassium fertilization had no effect.Ecophysiological models were developed to predict several banana acidity criteria during the pre and post harvest stages. pH and titratable acidity were predicted by a model of acid-base reactions; malate content by a model of vacuolar storage; and citrate content by a model of the TCA cycle. These models led to the identification of the key physiological processes that control banana acidity. Genotypic parameters were identified, which were related to the activity of the mitochondrial malic enzyme and of the malate mitochondrial carriers in the citrate model, as well as to the activity of the vacuolar proton pump, ATPase, in the malate model. The two models were also used to analyze the effects of fruit growth conditions on banana acidity.Combining the three models in a global model of banana acidity, and the possible use of this model for varietal improvement are discussed
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Leforestier, Diane. "Localisation de régions du génome du pommier contrôlant la variation de caractères de qualité du fruit et de résistance aux maladies : signatures de sélection et génétique d'association." Thesis, Angers, 2015. http://www.theses.fr/2015ANGE0051/document.
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Depuis la domestication du pommier, l’homme a progressivement sélectionné des variétés plus performantes, notamment pour la qualité du fruit, la productivité ou la résistance aux pathogènes. Les bases génétiques de ces caractères ont été explorées par cartographie en descendances F1 ne permettant d’explorer qu’une infime partie de la diversité génétique disponible.L’objectif de la thèse portait sur l’analyse des bases génétiques de caractères de qualité du fruit et de résistance du pommier à la tavelure et au feu bactérien dans des collections représentant une diversité plus large. Le génotypage de core collections de variétés anciennes s’est fait à l’aide de deux puces 8k et 480kSNPs ou grâce à du ré-séquençage de gènes. Des traces de différenciation génétique entre pommes à cidre et à couteau ont été identifiées et partiellement reliées à la voie des polyphénols. Après analyse de l’étendue du déséquilibre de liaison à large et fine échelle, une approche de génétique d’association a permis l’identification de régions génomiques associées à la variation de plusieurs caractères de qualité du fruit, dont le haut du groupe de liaison 16 rassemblant l’acidité (locus Ma), la fermeté, la jutosité et l’amertume (gène LAR). Pour la résistance au feu bactérien, une région contenant un homologue du gèneNPR1 (activateur de défenses) a été identifiée.Cette thèse a ainsi permis de préciser la localisation potentielle de QTLs identifiés préalablement par cartographie génétique et d’identifier de nouvelles ressources utiles dans de futurs programmes de sélection assistée par marqueursSince apple domestication, humans have progressively selected improved varieties, especially for traits linked with fruit quality, productivity or resistance to pathogens. The genetic bases underlying these traits have been explored thanks to genetic mapping in F1 segregating populations that only allows the study of a small part of the available genetic diversity. The aim of this work was to analyze the genetic bases of fruit quality and disease resistance against apple scab and fire blight, in collections of old apple varieties representing a much larger diversity. Genotyping of core collections was performed either with arrays of 8k and 480k SNPs or by resequencing of chosen genes. Signs of genetic differentiation were identified between cider and dessert apples and were partially linked to the polyphenols pathway. After studying linkage disequilibrium, both on a large and a small scale, an association genetics approach allowed the identification of genomic regions associated with the variation of several fruit quality traits. Especially, the top of linkage group 16 was found to be linked with acidity (locus Ma), firmness, juiciness and bitterness (LAR gene). Concerning the resistance of apple to fire blight, a region containing a homolog of the NPR1 gene (defense activator) was identified. This thesis allowed the refining of the putative localization of previously identified QTLs and the identification of new genetic resources that could be useful in future selection programs using marker assisted selection
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BACCICHET, IRINA. "GENOMIC APPROACHES AND PHENOTYPIC ANALYSES FOR IMPROVING THE SELECTION OF FRUIT QUALITY TRAITS IN PEACH [PRUNUS PERSICA L. (BATSCH.)] AND APRICOT (PRUNUS ARMENIACA L.)." Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/820680.
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Peach [Prunus persica L. (Batsch.)] and apricot (Prunus armeniaca L.) are two Prunus species developing delicious fruits and they are mostly grown in temperate areas of the world. Both species have been cultivated since ancient times, being greatly appreciated for their unique taste and benefits to human health. Peaches and apricots can be consumed either fresh or processed through canning or drying, depending on the preference of a specific region and the use-purpose. So far, many efforts have been done in enhancing disease and pest resistance, in increasing the environmental adaptability to sub-tropical areas, in extending the harvest season or in improving fruits appearance. However, consumers frequently complain about the lack of taste in peach and apricot fruits sold on markets, encouraging the ongoing breeding projects to include organoleptic properties among their objectives. Among all the fruit quality-related traits, acidity plays a pivotal role affecting both consumers’ and market acceptance. To match with market trends, an extensive characterization of peach and apricot fruits attributes under the highlighted necessity of renewing the varieties cultivated worldwide is required. In this thesis, a peach and apricot collection of 201 and 164 accessions, respectively, was screened for many important fruit organoleptic attributes, with a specific focus on acidity and organic acids content. Fruits acidity was titrated and ten organic acids (cis-aconitate, citrate, fumarate, galacturonate, malate, oxalate, quinate, shikimate, succinate and tartrate) separation was accomplished by HPLC technique coupled to UHPLC-HRMS validation. Analyses were performed on peach pulp and on apricot pulp and peel. The final aim was in-depth dissecting the peach and apricot panel for these organoleptic parameters to exploit the existing variability within their germplasm. Malate and citrate were the most abundant organic acids in both species, with pattern more genotype than year dependent. Results suggested that seasonality effects on fruits acidity and almost all the considered-organic acids were very low. Among the other organic acids, quinate and succinate reached large concentrations in peach and apricot, respectively, while tartrate was interestingly present more in apricot peel than pulp. The availability of a reference genome in peach has allowed to further characterize peach fruit quality traits. Over the past, peach fruits acidity has been partially elucidated at genetics level, identifying one major locus and making it a breeding target. Although the great advances, the selection accuracy and the long-time required for releasing new varieties on markets still hamper peach breeding progress. To in-depth unravel acidity trait and to speed up the selection of newly developed individuals in peach, a total of 1,190 accessions were genotyped for performing genomics analyses. Two different studies were carried out in this thesis: genomic selection (GS) and genome wide association studies (GWAS). Results confirmed that GS seems feasible in peach not only for acidity but also for organic acids content, in particular for patterns of malate and citrate. GWAS confirmed the presence of one major locus acting as dominant in peach fruits but revealed other significant associations on chromosomes 1, 7 and 8.
In summary, this thesis includes the first efforts in an in-depth and at multilevel dissection of acidity in peach and apricot, applying different approaches on a large panel of individuals. This thesis attempts to provide a complete overview with results that may be useful for future researches, studies and successful breeding programmes.
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Godoi, Rodrigo dos Santos. "Produtividade e qualidade do morangueiro em sistemas fechados de cultivo sem solo." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/4978.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorThe objective of the research was to determine the strawberry fruit yield and quality in three different closed soilless systems with two substrates. The experiment was conducted in a screenhouse in the Department of Fitotecnia at the Universidade Federal de Santa Maria, from April to November, 2006. The experimental set up was a 3 x 2 factorial design with four replications. Treatments were the three soilless systems and the two substrates. The soilless systems consist of plastic bags, plastic troughs and growing beds, all of them elevated from the soil. The substrates were an inert substrate (sand) and an organic substrate (Plantmax PXT®). Drip fertigation was used in the plastic bags, while subirrigation was done in the other two systems. A standard complete nutrient solution was utilized and there was not any disposal of it during the experiment. A significant interaction among substrates and systems was observed. In the case of the sand, best results were obtained with plastic troughs reaching a mean fruit yield of 122.09 t ha-1, which was 8.13% e 8.33% higher than the plastic bags and the growing beds, respectively. In the case of the organic substrate, the mean fruit yield in the system of growing beds (143.58 t ha-1) was 10.9% and 29.33% superior to the plastic bags and plastic troughs, respectively. Neither the soilless systems nor the substrates influenced the fruit quality characteristics of firmness, soluble solids and titratable acidity.
O objetivo do trabalho foi determinar a produtividade e qualidade do morangueiro em sistemas fechados de cultivo sem solo com substratos. O experimento foi conduzido dentro de um abrigo telado no Departamento de Fitotecnia da Universidade Federal de Santa Maria, entre abril e novembro de 2006. Os tratamentos foram constituídos por três sistemas de cultivo e dois substratos, em esquema fatorial 3x2, no delineamento inteiramente casualizado, com quatro repetições. Os sistemas de cultivo foram sacolas fertirrigadas por tubos gotejadores, calhas e leito de cultivo. Os substratos foram a areia como substrato inerte e o Plantmax PXT® como substrato orgânico, fertirrigados com solução nutritiva completa, sem descartes durante o período do experimento. Houve interação significativa entre os substratos e os sistemas. Na areia, destacou-se o cultivo nas calhas, com uma produtividade média de 122,09 t ha-1, sendo 8,13% e 8,33% superior às sacolas e ao leito de cultivo, respectivamente. No substrato orgânico, a média mais elevada foi equivalente a 143,58 t ha-1, obtida no leito de cultivo, superior às sacolas em 10,9% e às calhas em 29,33%. Não houve influência dos substratos nem dos sistemas sobre a qualidade da fruta, caracterizada através da firmeza, °Brix e acidez titulável.
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Faucher, Mélanie, and Mélanie Faucher. "Optimisation à l'échelle semi-industrielle de la désacidification du jus de canneberge par électrodialyse avec membranes bipolaires : impacts sur les performances et la composition du jus." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/29850.
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Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2018-2019Tableau d'honneur de la Faculté des études supérieures et postdoctorales, 2018-2019
La canneberge, petit fruit riche en composés phénoliques dont les anthocyanes et les proanthocyanidines, a de nombreux effets positifs sur la santé humaine. La consommation de jus de canneberge brut est un moyen d’en bénéficier, mais ce produit n’est pas toujours attrayant pour les consommateurs en raison de son manque de palatabilité et des possibles effets secondaires qu’il peut entraîner. Pour limiter ces désagréments, il est possible de désacidifier le jus de canneberge brut et parmi les méthodes actuellement disponibles, l’électrodialyse avec membranes bipolaires est particulièrement prometteuse. Jusqu’à présent les essais de désacidification du jus de canneberge par électrodialyse avec membranes bipolaires ont été réalisés sur des cellules à l’échelle laboratoire et en utilisant une nouvelle solution de récupération des acides organiques d’un essai à l’autre, ce qui limite son application à l’échelle industrielle. Le but de cette étude était, dans une optique d’industrialisation future, de tester le procédé à long terme sur une cellule semi-industrielle et de l’améliorer en réutilisant la solution de récupération d’un essai de désacidification à l’autre. Ainsi, des essais de désacidification du jus de canneberge ont été réalisés pour comptabiliser un total de 95 heures d’utilisation de la cellule semi-industrielle, sans poser de problème majeur au niveau de la résistance globale du système. De plus, le fait de réutiliser la solution de récupération des acides organiques n’a pas eu d’impact sur les caractéristiques physico-chimiques du jus désacidifié, et a permis des gains d’énergie allant jusqu’à 42,9 % après trois réutilisations, en plus de réduire les effluents du procédé. Ainsi, la mise à plus grande échelle et l’amélioration du procédé de désacidification du jus de canneberge par électrodialyse avec membranes bipolaires ont été concluantes et le transfert de la technologie en industrie est la prochaine étape à envisager.
La canneberge, petit fruit riche en composés phénoliques dont les anthocyanes et les proanthocyanidines, a de nombreux effets positifs sur la santé humaine. La consommation de jus de canneberge brut est un moyen d’en bénéficier, mais ce produit n’est pas toujours attrayant pour les consommateurs en raison de son manque de palatabilité et des possibles effets secondaires qu’il peut entraîner. Pour limiter ces désagréments, il est possible de désacidifier le jus de canneberge brut et parmi les méthodes actuellement disponibles, l’électrodialyse avec membranes bipolaires est particulièrement prometteuse. Jusqu’à présent les essais de désacidification du jus de canneberge par électrodialyse avec membranes bipolaires ont été réalisés sur des cellules à l’échelle laboratoire et en utilisant une nouvelle solution de récupération des acides organiques d’un essai à l’autre, ce qui limite son application à l’échelle industrielle. Le but de cette étude était, dans une optique d’industrialisation future, de tester le procédé à long terme sur une cellule semi-industrielle et de l’améliorer en réutilisant la solution de récupération d’un essai de désacidification à l’autre. Ainsi, des essais de désacidification du jus de canneberge ont été réalisés pour comptabiliser un total de 95 heures d’utilisation de la cellule semi-industrielle, sans poser de problème majeur au niveau de la résistance globale du système. De plus, le fait de réutiliser la solution de récupération des acides organiques n’a pas eu d’impact sur les caractéristiques physico-chimiques du jus désacidifié, et a permis des gains d’énergie allant jusqu’à 42,9 % après trois réutilisations, en plus de réduire les effluents du procédé. Ainsi, la mise à plus grande échelle et l’amélioration du procédé de désacidification du jus de canneberge par électrodialyse avec membranes bipolaires ont été concluantes et le transfert de la technologie en industrie est la prochaine étape à envisager.
Cranberry, a berry rich in phenolic compounds as anthocyanins and proanthocyanidins, has many beneficial effects on human health. To consume raw cranberry juice is a way to benefit from them, but that product presents a lack of palatability and can cause some side effects. To limit those inconveniences, raw juice can be deacidified and among all methods currently available, electrodialysis with bipolar membranes is very promising. Until now, essays to deacidify cranberry juice by electrodialysis with bipolar membranes were performed on laboratory scale cells using a fresh recovery solution from a deacidification essay to another. The aim of this work was to test the process on a larger scale for a longer period of time and to improve it by reusing the same recovery solution. Deacidification essays were performed in batch for a total of 95 hours on a semi-industrial cell and there was no major impact on the system global resistance. Furthermore, reusing the same recovery solution had no effect on the physicochemical properties of the deacidified juice, and energy savings up to 42.9% were recorded while the amount of waste produced was reduced. These positive results suggest the possibility to transfer the process at larger scale. Therefore, the next logical step for this project would be to scale-up the technology in factories for the industrial production of deacidified cranberry juice.
Cranberry, a berry rich in phenolic compounds as anthocyanins and proanthocyanidins, has many beneficial effects on human health. To consume raw cranberry juice is a way to benefit from them, but that product presents a lack of palatability and can cause some side effects. To limit those inconveniences, raw juice can be deacidified and among all methods currently available, electrodialysis with bipolar membranes is very promising. Until now, essays to deacidify cranberry juice by electrodialysis with bipolar membranes were performed on laboratory scale cells using a fresh recovery solution from a deacidification essay to another. The aim of this work was to test the process on a larger scale for a longer period of time and to improve it by reusing the same recovery solution. Deacidification essays were performed in batch for a total of 95 hours on a semi-industrial cell and there was no major impact on the system global resistance. Furthermore, reusing the same recovery solution had no effect on the physicochemical properties of the deacidified juice, and energy savings up to 42.9% were recorded while the amount of waste produced was reduced. These positive results suggest the possibility to transfer the process at larger scale. Therefore, the next logical step for this project would be to scale-up the technology in factories for the industrial production of deacidified cranberry juice.
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Pelletier, Stéphanie. "Optimisation de la désacidification électrodialytique du jus de canneberge par les champs électriques pulsés." Master's thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27676.
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La canneberge est bien reconnue pour les effets bénéfiques qu’elle peut apporter à la santé humaine. Cependant, la consommation de jus de canneberge est limitée car le jus a une grande acidité (teneur élevée en acides organiques) qui cause des effets secondaires tels la diarrhée, des vomissements et ballonnements. Par conséquent l’acidité du jus de canneberge doit être réduite pour améliorer la palatabilité du jus et diminuer les effets secondaires dus à sa consommation. La désacidification des jus, tels le jus de fruit de la passion et le jus de canneberge, par électrodialyse conventionnelle et électrodialyse avec membranes bipolaires par application d’un courant direct et continu s’est montrée efficace en comparaison avec les autres méthodes de désacidification telles les résines échangeuses d’ions et la précipitation au sel de calcium. L’objectif global de cette étude était d’appliquer les champs électriques pulsés (CÉPs) pendant l’électrodialyse avec membranes bipolaires pour désacidifier le jus de canneberge efficacement au niveau énergétique. Le CÉP consiste à appliquer un courant (Ton) et une pause de courant (Toff) pendant un temps donné consécutivement. Neuf conditions différentes ont été testées: 10s/2s, 1s/0.1s, 10s/0.1s, 6s/2s, 10s/1s, 2s/2s, 1s/1s, 6s/0.1s, 6s/1s. La désacidification du jus de canneberge a été 15% plus rapide avec les conditions de CÉPs de 1s/1s et 2s/2s en comparaison avec la désacidification à courant direct et continu et les autres combinaisons de pulse-pause. Pour ces 2 conditions, les migrations d’acide citrique et d’acide malique étaient plus rapides, ce qui a engendré un taux plus important de désacidification. Pour préserver l’authenticité du jus de canneberge, l’acide quinique doit être conservé, ce qui est le cas dans cette étude puisque l’acide quinique ne migre pas significativement quelles que soit les conditions testées. De plus, les PACs, les anthocyanes et les polyphénols totaux ont été conservés dans toutes les conditions de CÉP. Pour la première fois, l’efficacité d’appliquer du CÉP dans la désacidification de jus a été démontrée. L’électrodialyse avec membranes bipolaires pourrait être une méthode alternative verte et durable pour désacidifier des jus de fruits tout en préservant leurs caractéristiques organoleptiques et physico-chimiques.Cranberry is well recognized for its beneficial effects on human health, but the consumption of cranberry juice is limited due to its high acidity (high organic acid contents) which is the cause of undesirable side effects such as diarrhea, vomiting and bloating. Therefore, the acidity should be reduced to improve the palatability of the juice and to decrease the side effects. The deacidification of juices, such as citric acid solutions, passion juice and cranberry juice, by conventional electrodialysis and electrodialysis with bipolar membranes (EDBM) with coutinuous direct current (DC), has shown to be very effective in comparison with chemical methods such as calcium salt precipitation or ion-exchange resine. Therefore, the objective of this project is to apply pulsed electric field (PEF) during EDBM to deacidify cranberry juice. The PEF procedure consists of introducing to the process an electric pulse and a pause consecutively for a given time. Nine different pulse/pause combinations were tested: 10s/2s, 1s/0.1s, 10s/0.1s, 6s/2s, 10s/1s, 2s/2s, 1s/1s, 6s/0.1s, 6s/1s. The deacidification of cranberry juice was about 15% faster with PEFs for 1s/1s and 2s/2s conditions in comparison with deacidification with DC and other pulse-pause combinations. In these two conditions, the migration of citric and malic acids was faster, thus producing a more important rate of deacidification. To preserve the authenticity of the juice, the quinic acid must be conserved, which is the case in this study since the quinic acid did not migrated significantly in every conditions. Also, the PACs, anthocyanins and total polyphenols were preserved whatever the PEF conditions. It’s the first time that the efficiency of applying PEF for deacidification of juice was demonstrated. EDBM under PEF would be a green and sustainable alternative process to deacidify fruit juice and to preserve its organoleptic and physicochemical characteristics.
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Pellerin, Geneviève. "Impact de la désacidification du jus de canneberge par électrodialyse avec membrane bipolaire sur ses propriétés bénéfiques en lien avec la santé buccodentaire." Master's thesis, Université Laval, 2021. http://hdl.handle.net/20.500.11794/70282.
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La canneberge (Vaccinium macrocarpon) et ses produits dérivés renferment de fortes teneurs en composés phénoliques qui sont reconnus pour leurs bienfaits sur la santé buccodentaire. Cependant, la richesse en acides organiques du jus de canneberge lui confère une faible palatabilité et peut provoquer des effets secondaires indésirables. Le procédé d’électrodialyse avec membrane bipolaire (EDMB) permet le retrait sélectif des acides organiques du jus, et la production d’un jus pouvant être consommé sans dilution préalable. Ainsi, le projet de recherche visait à évaluer l’effet de la désacidification du jus de canneberge par EDMB sur les facteurs étiologiques des deux principales infections buccodentaires, soit la carie dentaire et la parodontite. À cet égard, les propriétés antibactériennes des jus brut et désacidifiés ont été évaluées vis-à-vis des colonisateurs primaires des tissus dentaires (Streptococcusgordonii, Streptococcus oralis, Streptococcus salivarius), des streptocoques cariogènes(Streptococcus mutans, Streptococcus sobrinus) et des bactéries parodontopathogènes clés(Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonasgingivalis). De même, l’impact de la désacidification du jus de canneberge sur les défenses de l’hôte (la barrière épithéliale gingivale et la réponse immunitaire) a été évalué dans des modèles in vitro. Les résultats de ces travaux ont montré que le retrait des acides organiques du jus de canneberge diminue ses propriétés bactéricides contre certaines espèces bactériennes à l’étude. Cependant, consommer un jus désacidifié plutôt qu’un jus brut dilué pourrait diminuer l’adhésion des bactéries aux tissus buccodentaires. D’autre part, la désacidification du jus a préservé l’intégrité de la barrière épithéliale gingivale comparativement au produit brut. Néanmoins, bien que les jus de canneberge non dilués aient démontré des propriétés anti-inflammatoires, ces dernières sont réduites suite à la désacidification du produit. Les résultats indiquent que la désacidification modérée du jus de canneberge par EDMB représente une stratégie prometteuse pour la production d’un jus favorisant le maintien d’une bonne santé buccodentaire.The high content in phenolic compounds found in cranberry (Vaccinium macrocarpon) is associated with well-known beneficial effects on oral health. However, cranberry juice (CJ)is rich in organic acids, which are responsible for the low palatability of the product and cancause gastrointestinal discomfort. Electrodialysis with bipolar membrane (EDBM) is an ecoefficient process that can be used for the deacidification of CJ, thus removing the requirement to dilute the product prior to consumption. This study aimed to evaluate how the deacidification of CJ by EDBM impacts its effects against the etiological factors of dental caries and periodontitis. The antibacterial activities of the raw and deacidifed CJ samples were assessed on commensal streptococci (Streptococcus gordonii, Streptococcus oralis,Streptococcus salivarius), cariogenic streptococci (Streptococcus mutans, Streptococcussobrinus), and key periodontopathogenic bacteria (Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis). Moreover, the impact of CJdeacidification on the host oral defenses (oral epithelial barrier function and host inflammatory response) was investigated in in vitro models.It appears from the results that removing organic acids from the product reduced the bactericidal activities of CJ against some bacterial species included in the study, though its hould be noted that deacidified CJ had generally higher anti-adherence properties comparedto its raw diluted counterpart. On the other hand, deacidification of CJ helped preserve the integrity of the oral epithelial barrier compared to the raw beverage. However, even though all undiluted CJ samples exerted anti-inflammatory properties, exposition to deacidified CJappears to lower this property in an oral epithelial cell model. Overall, this work brought evidence that a moderate deacidification of CJ by EDBM could allow the production of cranberry juice that provides benefits with respect to the maintenance of oral health
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Ngando, Ebongue Georges Franck. "Etude de la lipase endogène du mésocarpe du fruit du palmier à huile (Elaeis guineensis Jacq. ) : application à la sélection de lignées à faible acidité de l’huile." Bordeaux 2, 2009. http://www.theses.fr/2009BOR21616.
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Etienne, Audrey. "Quels Processus Physiologiques Pilotent l'Acidité de la Banane Dessert (sp. Musa) en Pré et Post Récolte? Modélisation Ecophysiologique et Analyse Expérimentale de l'Effet du Génotype et des Conditions de Croissance du Fruit." Phd thesis, Université des Antilles-Guyane, 2014. http://tel.archives-ouvertes.fr/tel-00985304.
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Chez la banane dessert, les saveurs sucrée et acide, caractéristiques importantes pour les consommateurs, sont pilotées par les teneurs en acides citrique et malique. Ce travail a donc porté sur l'étude des processus physiologiques qui pilotent l'accumulation de ces acides dans la pulpe de banane (Musa sp. AA) en combinant analyse expérimentale et modélisation écophysiologique. Nous nous sommes notamment intéressés à l'effet du génotype et des conditions de croissance du fruit en adoptant une approche intégrative liant les phases pré et post récolte. Les effets de la charge en fruit, de la fertilisation potassique, et du stade de récolte sur l'accumulation du citrate et du malate dans la pulpe ont été étudiés expérimentalement. La variabilité génotypique a été prise en compte en choisissant trois génotypes présentant des acidités contrastées à maturité. Des différences d'évolution des teneurs en acides, dues à des modifications métaboliques, ont été observées entre les génotypes pendant les phases pré et post récolte. Le stade de récolte a eu un effet significatif sur les teneurs en acides des fruits pendant la maturation post récolte. La charge en fruit et la fertilisation potassique n'en ont eu aucun. Des modèles écophysiologiques ont été développés pour prédire différents critères d'acidité de la banane en pré et post récolte. Le pH et l'acidité titrable ont été prédits par un modèle d'équilibres acido-basiques, la teneur en malate par un modèle de stockage vacuolaire, et la teneur en citrate par un modèle du cycle de Krebs. Ces modèles ont permis d'identifier les processus physiologiques clés qui pilotent l'acidité de la banane. Des paramètres génotypiques ont été identifiés liés à l'activité de l'enzyme malique mitochondriale et à celle des transporteurs mitochondriaux du malate pour le modèle citrate, et à l'activité des pompes à protons vacuolaire ATPases pour le modèle malate. Ces modèles ont également permis de disséquer l'effet des conditions de croissance du fruit sur l'acidité de la banane. L'intégration des modèles développés dans un modèle d'élaboration de l'acidité et son utilisation potentielle pour l'amélioration variétale sont discutées.
Book chapters on the topic "Fruit acidity"
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Zhang, Bo, and Yuepeng Han. "Genomics of Fruit Acidity and Sugar Content in Apple." In Compendium of Plant Genomes, 297–309. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-74682-7_14.
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Li, Hong. "Pre-Harvest Cultural Practices Affecting Postharvest Physiological Disorders, Minerals, and Titratable Acidity in Cucurbit Melon." In Postharvest Physiological Disorders in Fruits and Vegetables, 15–28. Boca Raton : Taylor & Francis, 2018.: CRC Press, 2019. http://dx.doi.org/10.1201/b22001-2.
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Ferullo, J. M., N. Montoya, and C. Triantaphylides. "Role of Ethylene in the Differential Induction of Acidic, Neutral and Basic Chitinases in Pericarps of Irradiated Cherry-Tomato Fruits." In Developments in Plant Pathology, 178. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1737-1_55.
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Klink, Michael J., Thembi Mphiwa, Ikechukwu P. Ejidike, Vusumzi E. Pakade, Neelan Laloo, and Fanyana M. Mtunzi. "Modification of QuEChERS Method for Acidic Pesticide (Imidacloprid) in Citrus Fruit and Some Processed Citrus Juices Using Ultra Performance Liquid Chromatography Coupled with a Triple Quad Detector (UPLC-TQD)." In Chemistry for a Clean and Healthy Planet, 429–46. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-20283-5_25.
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Natale, William, Danilo Eduardo, Serge-Etienne Parent, and Leon Etienne. "Soil Acidity and Liming in Tropical Fruit Orchards." In Soil Fertility. InTech, 2012. http://dx.doi.org/10.5772/53345.
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Shafqat, Waqar, Summar A. Naqvi, Rizwana Maqbool, Muhammad Salman Haider, Muhammad Jafar Jaskani, and Iqrar A. Khan. "Climate Change and Citrus." In Citrus [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95488.
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Climate change is the change in the statistical distribution of weather patterns that lasts for an extended period. Climate change and agriculture are interrelated processes and affect in many ways. Citrus fruits are one of the largest fruit crops in the world. Yield loss at a drastic level due to abiotic stress annually in which temperature and water stress are the main environmental factors. These factors cause biochemical, anatomical, physiological, and genetic changes in plant structure and lead to defective growth, development, and reproduction, which ultimately cause a reduction in the economic yield of the crop. An increase in temperature and water stress at critical phenological stages of citrus results in reduced tree fruit set, decrease in fruit growth and size, increase in fruit acidity, low tree yield, reduced fruit peel thickness, and pre-harvest fruit drop. Stomatal conductance and net carbon dioxide assimilation in citrus leaves can be reduced by super optimal leaf temperature. Water deficit reduces the transpiration rate, stomatal conductance by stomatal closure associated with ABA content and causes an abrupt decrease in photosynthesis and CO2 assimilation in citrus which reduce trees overall growth and production. Interventions in agronomic practices, breeding strategies, and biotechnological approaches can mitigate climate change effects on citrus. The groundwork against climate change is compulsory for better global livelihood and food security.
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Félix Hahn Schlam, Federico. "Robotic Heat Treatments for Mango and Prickly Pear Increase Shelf Life and Reduce Pathogen Infection." In Postharvest Technology - Recent Advances, New Perspectives and Applications [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101570.
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Mexico is the main exporter of mango fruits and prickly pears, so new postharvest techniques to increase shelf life are studied. Thermal treatments on both fruits can affect their cuticle so it was reviewed. When mango latex remains within the fruits, it avoids sap burn and decreases anthracnose and stem end rot infestation, so two systems were developed to minimize latex de-sapping. A gripper cuts stems 0.5 cm long and cauterizes them with a hot knife implement. A heating gun applied paraffin wax to mangoes without the stem end and protected them better against anthracnose lesions. Physicochemical analysis of several mango varieties was carried out after harvesting, at market place and after pedicel cutting and cauterizing. Keitt mangoes showed the lower quantity of total soluble solids (TSSs) and total acidity (TA). When the pedicel was cauterized, TSS dropped. Two grippers were developed to cryo-cauterize prickly pears as this system is more energy-efficient than hot cauterization. A six-finger gripper moved over a pneumatic actuator toward a dry ice chamber to optimize pear cryo-cauterization. Gripper’s strong grasping damaged the fruits due to excessive compression. TSS and TA of cryo-cauterized fruit remained constant during the three months of fruit storage.
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Paula, Daniele de Almeida, Ariana de Souza Soares, and Ellen Silva Lago Vanzela. "PROCESSING AND CHARACTERIZATION OF FRUIT JELLIES WITH THE ADDITION OF A CHOCOLATE FLAVORED PASTE." In Open Science Research X, 100–113. Editora Científica Digital, 2023. http://dx.doi.org/10.37885/230111732.
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The objective of this study was thus to develop fruit jellies with addition of chocolate. First a market study was carried out, where the consumer preference for strawberry and orange fruits for the preparation of the jellies was confirmed, as well as preference for chocolate inserted in the form of layers, creamy texture, and of milk flavor. Secondly, the jellies were elaborated and characterized. The moisture content and total soluble solids of both jellies were in agreement with the range commonly found for jellies. The values obtained for pH and acidity were slightly higher than the limits considered optimal for this product. In relation to the ash, protein and lipids contents, insertion of the chocolate paste led to the increase of these parameters. There was a decrease in the total sugar content, and consequently in the calorific value. After sensorial analysis, acceptance of jellies was verified.
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White, Robert E. "Site Selection and Soil Preparation." In Soils for Fine Wines. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195141023.003.0010.
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At the Pine Ridge winery in Napa Valley, California, a sign lists six essential steps in wine production. The first step reads . . . Determine the site—prepare the land, terrace the slopes for erosion control, provide drainage and manage soil biodiversity. . . . Determining the site means gathering comprehensive data on the local climate, topography, and geology, as well as the main soil types and their distribution. Traditionally, site determination was done using the knowledge and experience of individuals. Now it is possible to combine an expert’s knowledge with digital data on climate, parent material, topography, and soils in a GIS format to assess the biophysical suitability of land for wine grapes. Viticultural and soil experts together identify the key properties and assign weightings to these properties. An example of an Analytical Hierarchy Process is shown in figure 8.1. In this approach, both objective and subjective data were pooled and evaluated to decide the suitability of land for viticulture in West Gippsland, Victoria. In this region with a relatively uniform, mild climate, soil was given a 70% weighting, and the important soil properties were identified as depth, drainage, sodicity, texture, and pH. But in other areas, with another group of experts, a different set of key properties and weightings may well be identified. For example, a similar approach used in Virginia, in the United States, gave only a 25% weighting to soil and 30% to elevation (which affected temperature, a critical factor governing growth rate and ripening) (Boyer and Wolf 2000). This kind of approach can be refined to indicate site suitability for a particular variety within a region of given macroclimate. For example, Barbeau et al. (1998) assessed the suitability of sites in the Loire Valley, France, for the cultivar Cabernet Franc, using an index of “precocity.” Such an index is related to the ability of the fruit to accumulate sugar and anthocyanins and to attain a favorable acidity.
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sevenpub, sevenpub. "Quality characteristics of tomatoes grape type as function of packaging and storage." In METHODOLOGY FOCUSED ON THE AREA OF INTERDISCIPLINARITY- V1. Seven Editora, 2023. http://dx.doi.org/10.56238/methofocusinterv1-083.
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One of the ways of preserving tomato fruits is the use of packages that have the function of controlling or minimizing degradation processes, enabling fruits to maintain quality characteristics even for consumers. This work aimed to evaluate the influence of active packaging (incorporated from ethylene absorbers) on the preservation of quality attributes, bioactive compound contents, and antioxidant activity of grape tomatoes during storage. The experimental design was completely randomized involving 2 treatments (active packaging and PET packaging), 5 storage times (0, 5, 10, 15, and 20 days), and 4 replications. The following were evaluated: pH, total titratable acidity, total soluble solids, Ratio, firmness, instrumental color, loss of fresh mass, lycopene, total phenolic composites, vitamin C, and antioxidant activity. The lycopene content of fruits packed in active packaging increased (29.8 to 48.7 μg.100 g-1 in 20 days of storage and decreased in the fruits packed in PET packages during this same period. There was the degradation of vitamin C, whose average contents of the stored fruits, regardless of the packaging ranged from 21.4 to 15.9 mg.100 g -1. The definition of the best packaging used depends on the storage period submitted. For the conservation of mass and lycopene content for 20 days at 16 ºC ± 2 the active packaging showed the best result.
Conference papers on the topic "Fruit acidity"
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Green, Hilary, and Selina Wang. "Avocado oil chemical composition varies with harvest time, growing region, and fruit quality, demonstrating important considerations for standard development." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/xako6609.
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Avocado oil currently does not have standards in place to regulate its purity or quality. To set appropriate standards, factors that impact the chemical composition of avocado oil need to be better understood. To help address this, fruits from different regions were harvested throughout the year and processed using lab-scale equipment into oil. The oils’ purity (fatty acid profile, sterols, and triacylglycerols) and quality (free fatty acidity, peroxide value, and specific extinction in UV) were determined in addition to minor components such as tocopherols. It was discovered that growing region and harvest time had a greater impact on fatty acid and sterols profiles than using whole fruit verses only flesh to process the oil. The same standards are set for all avocado oils regardless of the country of origin, this finding indicates it will be important to ensure standards can accommodate oils from different regions. In addition, using poor quality fruit to make oil caused a significant increase in the free fatty acidity compared to using good quality fruit at the time of processing. This work determined a baseline for avocado oil quality parameters by extracting oil from ripe, good quality fruit, which can in turn can inform reasonable limits for avocado oil quality standards.
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Marlindayanti and Nur Adiba Hanum. "The Fruit of Seated (Melastomamalabathricum L.) As Agent for Detecting the Age and Acidity of Dental Plaque." In First International Conference on Health, Social Sciences and Technology (ICOHSST 2020). Paris, France: Atlantis Press, 2021. http://dx.doi.org/10.2991/assehr.k.210415.051.
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Suriati, Luh, I. Gede Pasek Mangku, Luh Kade Datrini, Hanilyn Hidalgo, and Josephine Red. "Effect of Aloe-gel and bignay fruit proportions to acidity, total dissolved solids, and color of Aloe-bignay beverage." In Proceedings of the 1st Warmadewa International Conference on Science, Technology and Humanity, WICSTH 2021, 7-8 September 2021, Denpasar, Bali, Indonesia. EAI, 2022. http://dx.doi.org/10.4108/eai.7-9-2021.2317714.
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Gea, Saharman, Amir Hamzah Siregar, Emma Zaidar, Mahyuni Harahap, and Yurika Almanda Perangin-Angin. "Lignin Isolation from Oil Palm Empty Fruit Bunches (OPEFB) by Acidic Method." In The International MIPAnet Conference on Science and Mathematics (IMC-SciMath). SCITEPRESS - Science and Technology Publications, 2019. http://dx.doi.org/10.5220/0010613900002775.
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Paraschiv, Alina-Nicoleta, Milica Dima, Aurelia Diaconu, Elena Ciuciuc, and Mihaela Croitoru. "RESEARCH ON THE BEHAVIOR OF AN ASSORTMENT OF BELL PEPPER ON THE SANDY SOILS IN SOUTH-WEST OLTENIA ACCORDING TO THE CULTIVATION METHOD USED." In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/40.
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The pedo-climatic conditions specific to sandy soils in southwest Oltenia determine differences in performing different phenophases of growth and development of plants, both between varieties and in the physiological behavior of the same variety under different yield conditions. Therefore, at the Dăbuleni Research and Development Station for Plant Culture on Sands, research was carried out on some physiological, biochemical and production processes at five varieties of bell peppers cultivated in the open fields and solar. Determinations of photosynthesis, foliar transpiration, the biochemical composition of fruits, quantity, and quality of bell pepper production were performed. The physiological and biochemical processes studied were influenced by the environmental conditions specific to each cultivation method, but also by the studied variables. Of the 5 varieties studied, the best results on the biochemical composition of the fruits were recorded at the Artim variety (8.83% total dry substance, 4.60% soluble dry substance, 0.19% acidity, 3.80% carbohydrate and 36.96% vitamin C). The production was between 15,387 t / ha for open-field plants and 108,574 t / ha for plants grown in the solar, the differences between the two cultivation methods being statistically assured as distinctly significant.
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Pratama, Wahyu Rangga, Genoveva Audrey Annabella Koo, and Robertas Nugroho Perwiro Atmojo. "WiroTomo SourDuino: Instrument for Measuring the Acidic Level of Home-Industry Fruit Juice Production." In 2021 International Conference on Software Engineering & Computer Systems and 4th International Conference on Computational Science and Information Management (ICSECS-ICOCSIM). IEEE, 2021. http://dx.doi.org/10.1109/icsecs52883.2021.00113.
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Morene, O. Caceres, D. M. Martinez Gila, D. Aguilera Puerto, J. Gamez Garcia, and J. Gomez Ortega. "Automatic determination of peroxides and acidity of olive oil using machine vision in olive fruits before milling process." In 2015 IEEE International Conference on Imaging Systems and Techniques (IST). IEEE, 2015. http://dx.doi.org/10.1109/ist.2015.7294543.
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Faqih, P., F. Nurosyid, and T. Kusumaningsih. "Effect of acidic level (pH) of red dragon fruit (Hylocereus costaricencis) peels extract on DSSC efficiency." In THE 14TH JOINT CONFERENCE ON CHEMISTRY 2019. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0005686.
Full textReports on the topic "Fruit acidity"
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Sadka, Avi, Mikeal L. Roose, and Yair Erner. Molecular Genetic Analysis of Citric Acid Accumulation in Citrus Fruit. United States Department of Agriculture, March 2001. http://dx.doi.org/10.32747/2001.7573071.bard.
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The acid content of the juice sac cells is a major determinant of maturity and fruit quality in citrus. Many citrus varieties accumulate acid in concentrations that exceed market desires, reducing grower income and consumer satisfaction. Pulp acidity is thought to be dependent on two mechanisms: the accumulation of citric acid in the vacuoles of the juice sac cells, and acidification of the vacuole. The major aim of the project was to direct effort toward understanding the mechanism of citric acid accumulation in the fruit. The following objectives were suggested: Measure the activity of enzymes likely to be involved in acid accumulation and follow their pattern of expression in developing fruit (Sadka, Erner). Identify and clone genes which are associated with high and low acid phenotypes and with elevated acid level (Roose, Sadka, Erner). Convert RAPD markers that map near a gene that causes low acid phenotype to specific co dominant markers (Roose). Use genetic co segregation to test whether specific gene products are responsible for low acid phenotype (Roose and Sadka). Objective 1 was fully achieved. Most of the enzymes of organic acid metabolism were cloned from lemon pulp. Their expression was studied during fruit development in low and high acid varieties. The activity and expression of citrate synthase, aconitase and NADP-isocitrate dehydrogenase (IDH) were studied in detail. The role that each enzyme plays in acid accumulation and decline was evaluated. As a result, a better understanding of the metabolic changes that contribute to acid accumulation was achieved. It was found that the activity of the mitochondrial aconitase is greatly reduced early in high-acid fruits, but not in acidless ones, suggesting that this enzyme plays an important role in acid accumulation. In addition, it was demonstrated that increases in the cytosolic forms of aconitase and NADP-IDH towards fruit maturation play probably a major role in acid decline. Our studies also demonstrated that the two mechanisms that contribute to fruit acidity, vacuolar acidification and citric acid accumulation, are independent, although they are tightly co-regulated. Additional, we demonstrated that sodium arsenite, which reduce fruit acidity, causes a transient inhibition in the activity of citrate synthase, but an induction in the gene expression. This part of the work has resulted in 4 papers. Objective 3 was also fully achieved. Using bulked segregant analysis, three random amplified polymorphic DNA (RAPD) markers were identified as linked to acitric, a gene controlling the acidless phenotype of pummelo 2240. One of them, which mapped 1.2 cM from acitric was converted into sequence characterized amplified region (SCAR marker, and into co dominant restriction length polymorphism (RFLP) marker. These markers were highly polymorphic among 59 citrus accessions, and therefore, they should be useful for selecting seedling progeny heterozygous for acitric in nearly all crosses between pummelo 2240 and other citrus genotypes. This part of the project resulted in one paper. Objective 4 was also fully achieved. Clones isolated by the Israeli group were sent to the American laboratory for co segregation analysis. However, none of them seemed to co segregate with the low acid phenotype. Both laboratories invested much effort in achieving the goals of Objective 2, namely the isolation of genes that are elevated in expression in low and high acid phenotypes, and in tissue cultures treated with arsenite (a treatment which reduces fruit acidity). However, conventional differential display and restriction fragment differential display analyses could not identify any differentially expressed genes. The isolation of such genes was the major aim of a continuation project, which was recently submitted.
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Blumwald, Eduardo, and Avi Sadka. Sugar and Acid Homeostasis in Citrus Fruit. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7697109.bard.
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Citrus fruit quality standards have been determined empirically, depending on species and on the particular growing regions. In general, the TSS (total soluble solids) to total acidity (TA) ratio determines whether citrus fruit can be marketed. Soluble sugars account for most of the TSS during harvest while TA is determined almost solely by the citric acid content, which reaches levels of 1-5% by weight in many cultivated varieties. Acid and sugar homeostasis in the fruit is critical for the management of existing cultivars, the development of new cultivars, the improvement of pre- and post-harvest strategies and the control of fruit quality and disorders. The current proposal (a continuation of a previous proposal) aimed at: (1) completing the citrus fruit proteome and metabolome, and establish a citrus fruit functional database, (2) further characterization of the control of fruit acidity by studying the regulation of key steps affecting citrate metabolism, and determine the fate of citrate during acid decline stage, and (3) Studying acid and sugar homeostasis in citrus fruits by characterizing transport mechanisms across membranes. These aims were completed as the following: (1) Our initial efforts were aimed at the characterization and identification of citric acid transporters in citrus juice cells. The identification of citrate transporters at the vacuole of the citrus juice cell indicated that the steady-state citrate cytosolic concentration and the action of the cytosolic aconitase were key elements in establishing the pH homeostat in the cell that regulates the metabolic shift towards carbon usage in the fruit during the later stages of fruit development. We focused on the action of aconitase, the enzyme mediating the metabolic use of citric acid in the cells, and identified processes that control carbon fluxes in developing citrus fruits that control the fruit acid load; (2) The regulation of aconitase, catalyzing a key step in citrate metabolism, was further characterized by using two inhibitors, citramalte and oxalomalte. These compounds significantly increased citrate content and reduced the enzyme’s activity. Metabolite profiling and changes of amino-acid metabolizing enzymes in oxalomalate- treated cells suggested that the increase in citrate, caused by aconitase inhibition, induces amino acid synthesis and the GABA shunt, in accordance with the suggested fate of citrate during the acid decline stage in citrus fruit. (3) We have placed a considerable amount of time on the development of a citrus fruit proteome that will serve to identify all of the proteins in the juice cells and will also serve as an aid to the genomics efforts of the citrus research community (validating the annotation of the fruit genes and the different ESTs). Initially, we identified more than 2,500 specific fruit proteins and were able to assign a function to more than 2,100 proteins (Katz et al., 2007). We have now developed a novel Differential Quantitative LC-MS/MS Proteomics Methodology for the identification and quantitation of key biochemical pathways in fruits (Katz et al., 2010) and applied this methodology to identify determinants of key traits for fruit quality (Katz et al., 2011). We built “biosynthesis maps” that will aid in defining key pathways associated with the development of key fruit quality traits. In addition, we constructed iCitrus (http://wiki.bioinformatics.ucdavis.edu/index.php/ICitrus), a “functional database” that is essentially a web interface to a look-up table that allows users to use functional annotations in the web to identify poorly annotated citrus proteins. This resource will serve as a tool for growers and field extension specialists.
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Blumwald, Eduardo, and Avi Sadka. Citric acid metabolism and mobilization in citrus fruit. United States Department of Agriculture, October 2007. http://dx.doi.org/10.32747/2007.7587732.bard.
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Accumulation of citric acid is a major determinant of maturity and fruit quality in citrus. Many citrus varieties accumulate citric acid in concentrations that exceed market desires, reducing grower income and consumer satisfaction. Citrate is accumulated in the vacuole of the juice sac cell, a process that requires both metabolic changes and transport across cellular membranes, in particular, the mitochondrial and the vacuolar (tonoplast) membranes. Although the accumulation of citrate in the vacuoles of juice cells has been clearly demonstrated, the mechanisms for vacuolar citrate homeostasis and the components controlling citrate metabolism and transport are still unknown. Previous results in the PIs’ laboratories have indicated that the expression of a large number of a large number of proteins is enhanced during fruit development, and that the regulation of sugar and acid content in fruits is correlated with the differential expression of a large number of proteins that could play significant roles in fruit acid accumulation and/or regulation of acid content. The objectives of this proposal are: i) the characterization of transporters that mediate the transport of citrate and determine their role in uptake/retrieval in juice sac cells; ii) the study of citric acid metabolism, in particular the effect of arsenical compounds affecting citric acid levels and mobilization; and iii) the development of a citrus fruit proteomics platform to identify and characterize key processes associated with fruit development in general and sugar and acid accumulation in particular. The understanding of the cellular processes that determine the citrate content in citrus fruits will contribute to the development of tools aimed at the enhancement of citrus fruit quality. Our efforts resulted in the identification, cloning and characterization of CsCit1 (Citrus sinensis citrate transporter 1) from Navel oranges (Citrus sinesins cv Washington). Higher levels of CsCit1 transcripts were detected at later stages of fruit development that coincided with the decrease in the juice cell citrate concentrations (Shimada et al., 2006). Our functional analysis revealed that CsCit1 mediates the vacuolar efflux of citrate and that the CsCit1 operates as an electroneutral 1CitrateH2-/2H+ symporter. Our results supported the notion that it is the low permeable citrateH2 - the anion that establishes the buffer capacity of the fruit and determines its overall acidity. On the other hand, it is the more permeable form, CitrateH2-, which is being exported into the cytosol during maturation and controls the citrate catabolism in the juice cells. Our Mass-Spectrometry-based proteomics efforts (using MALDI-TOF-TOF and LC2- MS-MS) identified a large number of fruit juice sac cell proteins and established comparisons of protein synthesis patterns during fruit development. So far, we have identified over 1,500 fruit specific proteins that play roles in sugar metabolism, citric acid cycle, signaling, transport, processing, etc., and organized these proteins into 84 known biosynthetic pathways (Katz et al. 2007). This data is now being integrated in a public database and will serve as a valuable tool for the scientific community in general and fruit scientists in particular. Using molecular, biochemical and physiological approaches we have identified factors affecting the activity of aconitase, which catalyze the first step of citrate catabolism (Shlizerman et al., 2007). Iron limitation specifically reduced the activity of the cytosolic, but not the mitochondrial, aconitase, increasing the acid level in the fruit. Citramalate (a natural compound in the juice) also inhibits the activity of aconitase, and it plays a major role in acid accumulation during the first half of fruit development. On the other hand, arsenite induced increased levels of aconitase, decreasing fruit acidity. We have initiated studies aimed at the identification of the citramalate biosynthetic pathway and the role(s) of isopropylmalate synthase in this pathway. These studies, especially those involved aconitase inhibition by citramalate, are aimed at the development of tools to control fruit acidity, particularly in those cases where acid level declines below the desired threshold. Our work has significant implications both scientifically and practically and is directly aimed at the improvement of fruit quality through the improvement of existing pre- and post-harvest fruit treatments.
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Engel, Bernard, Yael Edan, James Simon, Hanoch Pasternak, and Shimon Edelman. Neural Networks for Quality Sorting of Agricultural Produce. United States Department of Agriculture, July 1996. http://dx.doi.org/10.32747/1996.7613033.bard.
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The objectives of this project were to develop procedures and models, based on neural networks, for quality sorting of agricultural produce. Two research teams, one in Purdue University and the other in Israel, coordinated their research efforts on different aspects of each objective utilizing both melons and tomatoes as case studies. At Purdue: An expert system was developed to measure variances in human grading. Data were acquired from eight sensors: vision, two firmness sensors (destructive and nondestructive), chlorophyll from fluorescence, color sensor, electronic sniffer for odor detection, refractometer and a scale (mass). Data were analyzed and provided input for five classification models. Chlorophyll from fluorescence was found to give the best estimation for ripeness stage while the combination of machine vision and firmness from impact performed best for quality sorting. A new algorithm was developed to estimate and minimize training size for supervised classification. A new criteria was established to choose a training set such that a recurrent auto-associative memory neural network is stabilized. Moreover, this method provides for rapid and accurate updating of the classifier over growing seasons, production environments and cultivars. Different classification approaches (parametric and non-parametric) for grading were examined. Statistical methods were found to be as accurate as neural networks in grading. Classification models by voting did not enhance the classification significantly. A hybrid model that incorporated heuristic rules and either a numerical classifier or neural network was found to be superior in classification accuracy with half the required processing of solely the numerical classifier or neural network. In Israel: A multi-sensing approach utilizing non-destructive sensors was developed. Shape, color, stem identification, surface defects and bruises were measured using a color image processing system. Flavor parameters (sugar, acidity, volatiles) and ripeness were measured using a near-infrared system and an electronic sniffer. Mechanical properties were measured using three sensors: drop impact, resonance frequency and cyclic deformation. Classification algorithms for quality sorting of fruit based on multi-sensory data were developed and implemented. The algorithms included a dynamic artificial neural network, a back propagation neural network and multiple linear regression. Results indicated that classification based on multiple sensors may be applied in real-time sorting and can improve overall classification. Advanced image processing algorithms were developed for shape determination, bruise and stem identification and general color and color homogeneity. An unsupervised method was developed to extract necessary vision features. The primary advantage of the algorithms developed is their ability to learn to determine the visual quality of almost any fruit or vegetable with no need for specific modification and no a-priori knowledge. Moreover, since there is no assumption as to the type of blemish to be characterized, the algorithm is capable of distinguishing between stems and bruises. This enables sorting of fruit without knowing the fruits' orientation. A new algorithm for on-line clustering of data was developed. The algorithm's adaptability is designed to overcome some of the difficulties encountered when incrementally clustering sparse data and preserves information even with memory constraints. Large quantities of data (many images) of high dimensionality (due to multiple sensors) and new information arriving incrementally (a function of the temporal dynamics of any natural process) can now be processed. Furhermore, since the learning is done on-line, it can be implemented in real-time. The methodology developed was tested to determine external quality of tomatoes based on visual information. An improved model for color sorting which is stable and does not require recalibration for each season was developed for color determination. Excellent classification results were obtained for both color and firmness classification. Results indicted that maturity classification can be obtained using a drop-impact and a vision sensor in order to predict the storability and marketing of harvested fruits. In conclusion: We have been able to define quantitatively the critical parameters in the quality sorting and grading of both fresh market cantaloupes and tomatoes. We have been able to accomplish this using nondestructive measurements and in a manner consistent with expert human grading and in accordance with market acceptance. This research constructed and used large databases of both commodities, for comparative evaluation and optimization of expert system, statistical and/or neural network models. The models developed in this research were successfully tested, and should be applicable to a wide range of other fruits and vegetables. These findings are valuable for the development of on-line grading and sorting of agricultural produce through the incorporation of multiple measurement inputs that rapidly define quality in an automated manner, and in a manner consistent with the human graders and inspectors.
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Sionov, Edward, Nancy Keller, and Shiri Barad-Kotler. Mechanisms governing the global regulation of mycotoxin production and pathogenicity by Penicillium expansum in postharvest fruits. United States Department of Agriculture, January 2017. http://dx.doi.org/10.32747/2017.7604292.bard.
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The original objectives of the study, as defined in the approved proposal, are: To characterize the relationship of CreA and LaeA in regulation of P T production To understand how PacC modulates P. expansumpathogenicity on apples To examine if other secondary metabolites are involved in virulence or P. expansumfitness To identify the signaling pathways leading to PAT synthesis Penicilliumexpansum, the causal agent of blue mould rot, is a critical health concern because of the production of the mycotoxinpatulin (PAT) in colonized apple fruit tissue. Although PAT is produced by many Penicilliumspecies, the factors activating its biosynthesis were not clear. This research focused on host and fungal mechanisms of activation of LaeA (the global regulator of secondary metabolism), PacC (the global pH modulator) and CreA (the global carbon catabolite regulator) on PAT synthesis with intention to establish P. expansumas the model system for understanding mycotoxin synthesis in fruits. The overall goal of this proposal is to identify critical host and pathogen factors that mechanistically modulate P. expansumgenes and pathways to control activation of PAT production and virulence in host. Several fungal factors have been correlated with disease development in apples, including the production of PAT, acidification of apple tissue by the fungus, sugar content and the global regulator of secondary metabolism and development, LaeA. An increase in sucrose molarity in the culture medium from 15 to 175 mM negatively regulated laeAexpression and PAT accumulation, but, conversely, increased creAexpression, leading to the hypothesis that CreA could be involved in P. expansumPAT biosynthesis and virulence, possibly through the negative regulation of LaeA. We found evidence for CreAtranscriptional regulation of laeA, but this was not correlated with PAT production either in vitro or in vivo, thus suggesting that CreA regulation of PAT is independent of LaeA. Our finding that sucrose, a key ingredient of apple fruit, regulates PAT synthesis, probably through suppression of laeAexpression, suggests a potential interaction between CreA and LaeA, which may offer control therapies for future study. We have also identified that in addition to PAT gene cluster, CreA regulates other secondary metabolite clusters, including citrinin, andrastin, roquefortine and communesins, during pathogenesis or during normal fungal growth. Following creation of P. expansumpacCknockout strain, we investigated the involvement of the global pH regulator PacC in fungal pathogenicity. We demonstrated that disruption of the pH signaling transcription factor PacC significantly decreased the virulence of P. expansumon deciduous fruits. This phenotype is associated with an impairment in fungal growth, decreased accumulation of gluconic acid and reduced synthesis of pectolytic enzymes. We showed that glucose oxidase- encoding gene, which is essential for gluconic acid production and acidification during fruit colonization, was significantly down regulated in the ΔPepacCmutant, suggesting that gox is PacC- responsive gene. We have provided evidence that deletion of goxgene in P. expansumled to a reduction in virulence toward apple fruits, further indicating that GOX is a virulence factor of P. expansum, and its expression is regulated by PacC. It is also clear from the present data that PacC in P. expansumis a key factor for the biosynthesis of secondary metabolites, such as PAT. On the basis of RNA-sequencing (RNA-seq) analysis and physiological experimentation, the P. expansumΔlaeA, ΔcreAand ΔpacCmutants were unable to successfully colonize apples for a multitude of potential mechanisms including, on the pathogen side, a decreased ability to produce proteolytic enzymes and to acidify the environment and impaired carbon/nitrogen metabolism and, on the host side, an increase in the oxidative defence pathways. Our study defines these global regulatory factors and their downstream signalling pathways as promising targets for the development of strategies to fight against this post-harvest pathogen.
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Prusky, Dov, Nancy P. Keller, and Amir Sherman. global regulation of mycotoxin accumulation during pathogenicity of Penicillium expansum in postharvest fruits. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7600012.bard.
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Background to the topic- Penicilliumas a postharvest pathogen and producer of the mycotoxin PAT. Penicilliumspp. are destructive phytopathogens, capable of causing decay in many deciduous fruits, during postharvest handling and storage; and the resulting losses can amount to 10% of the stored produce and the accumulation of large amounts of the mycotoxinpatulin. The overall goal of this proposal is to identify critical host and pathogen factors that modulate P. expansummycotoxin genes and pathways which are required for PAT production and virulence. Our preliminary results indicated that gluconic acid are strongly affecting patulin accumulation during colonization. P. expansumacidifies apple fruit tissue during colonization in part through secretion of gluconic acid (GLA). Several publications suggested that GLA accumulation is an essential factor in P. expansumpathogenicity. Furthermore, down regulation of GOX2 significantly reduced PAT accumulation and pathogenicity. PAT is a polyketide and its biosynthesis pathway includes a 15-gene cluster. LaeA is a global regulator of mycotoxin synthesis. It is now known that patulin synthesis might be subjected to LaeA and sometimes by environmental sensing global regulatory factors including the carbon catabolite repressor CreA as well as the pH regulator factor PacC and nitrogen regulator AreA. The mechanisms by which LaeA regulates patulin synthesis was not fully known and was part of our work. Furthermore, the regulatory system that controls gene expression in accordance with ambient pH was also included in our work. PacC protein is in an inactive conformation and is unable to bind to the promoter sites of the target genes; however, under alkaline growth conditions activated PacC acts as both an activator of alkaline-expressed genes and a repressor of acid-expressed genes. The aims of the project- This project aims to provide new insights on the roles of LaeA and PacC and their signaling pathways that lead to GLA and PAT biosynthesis and pathogenicity on the host. Specifically, our specific aims were: i) To elucidate the mechanism of pH-controlled regulation of GLA and PAT, and their contribution to pathogenesis of P. expansum. We are interested to understanding how pH and/or GLA impact/s under PacC regulation affect PAT production and pathogenesis. ii) To characterize the role of LaeA, the global regulator of mycotoxin production, and its effect on PAT and PacC activity. iii) To identify the signaling pathways leading to GLA and PAT synthesis. Using state- of-the-art RNAseq technologies, we will interrogate the transcriptomes of laeAand pacCmutants, to identify the common signaling pathways regulating synthesis of both GLA and PAT. Major conclusions, solutions, achievements- In our first Aim our results demonstrated that ammonia secreted at the leading edge of the fungal colony induced transcript activation of the global pH modulator PacC and PAT accumulation in the presence of GLA. We assessed these parameters by: (i) direct exogenous treatment of P. expansumgrowing on solid medium; (ii) direct exogenous treatment on colonized apple tissue; (iii) growth under self-ammonia production conditions with limited carbon; and (iv) analysis of the transcriptional response to ammonia of the PAT biosynthesis cluster. Ammonia induced PAT accumulation concurrently with the transcript activation of pacCand PAT biosynthesis cluster genes, indicating the regulatory effect of ammonia on pacCtranscript expression under acidic conditions. Transcriptomic analysis of pH regulated processes showed that important genes and BARD Report - Project 4773 Page 2 of 10 functionalities of P. expansumwere controlled by environmental pH. The differential expression patterns of genes belonging to the same gene family suggest that genes were selectively activated according to their optimal environmental conditions to enable the fungus to cope with varying conditions and to make optimal use of available enzymes. Concerning the second and third Aims, we demonstrated that LaeA regulates several secondary metabolite genes, including the PAT gene cluster and concomitant PAT synthesis invitro. Virulence studies of ΔlaeAmutants of two geographically distant P. expansumisolates (Pe-21 from Israel and Pe-T01 from China) showed differential reduction in disease severity in freshly harvested fruit ranging from no reduction for Ch-Pe-T01 strains in immature fruit to 15–25% reduction for both strains in mature fruit, with the ΔlaeAstrains of Is-Pe-21 always showing a greater loss in virulence. Results suggest the importance of LaeA regulation of PAT and other secondary metabolites on pathogenicity. Our work also characterized for the first time the role of sucrose, a key nutritional factor present in apple fruit, as a negative regulator of laeAexpression and consequent PAT production in vitro. This is the first report of sugar regulation of laeAexpression, suggesting that its expression may be subject to catabolite repression by CreA. Some, but not all of the 54 secondary metabolite backbone genes in the P. expansumgenome, including the PAT polyketide backbone gene, were found to be regulated by LaeA. Together, these findings enable for the first time a straight analysis of a host factor that potentially activates laeAand subsequent PAT synthesis.
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Brandl, Maria T., Shlomo Sela, Craig T. Parker, and Victor Rodov. Salmonella enterica Interactions with Fresh Produce. United States Department of Agriculture, September 2010. http://dx.doi.org/10.32747/2010.7592642.bard.
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The emergence of food-borne illness outbreaks linked to the contamination of fruits and vegetables is a great concern in industrialized countries. The current lack of control measures and effective sanitization methods prompt the need for new strategies to reduce contamination of produce. Our ability to assess the risk associated with produce contamination and to devise innovative control strategies depends on the identification of critical determinants that affect the growth and the persistence of human pathogens on plants. Salmonella enterica, a common causal agent of illness linked to produce, has the ability to colonize and persist on plants. Thus, our main objective was to identify plant-inducible genes that have a role in the growth and/or persistence of S. enterica on postharvest lettuce. Our findings suggest that in-vitro biofilm formation tests may provide a suitable model to predict the initial attachment of Salmonella to cut-romaine lettuce leaves and confirm that Salmonella could persist on lettuce during shelf-life storage. Importantly, we found that Salmonella association with lettuce increases its acid-tolerance, a trait which might be correlated with an enhanced ability of the pathogen to pass through the acidic barrier of the stomach. We have demonstrated that Salmonella can internalize leaves of iceberg lettuce through open stomata. We found for the first time that internalization is an active bacterial process mediated by chemotaxis and motility toward nutrient produced in the leaf by photosynthesis. These findings may provide a partial explanation for the failure of sanitizers to efficiently eradicate foodborne pathogens in leafy greens and may point to a novel mechanism utilized by foodborne and perhaps plant pathogens to colonize leaves. Using resolvase in vivo expression technology (RIVET) we have managed to identify multiple Salmonella genes, some of which with no assigned function, which are involved in attachment to and persistence of Salmonella on lettuce leaves. The precise function of these genes in Salmonella-leaf interactions is yet to be elucidated. Taken together, our findings have advanced the understanding of how Salmonella persist in the plant environment, as well as the potential consequences upon ingestion by human. The emerging knowledge opens new research directions which should ultimately be useful in developing new strategies and approaches to reduce leaf contamination and enhance the safety of fresh produce.