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Lactic acid bacteria (LAB) have been shown to prevent the growth and activity of several postharvest pathogen fungi in fruit and vegetables because of their ability to produce antimicrobial metabolites. Edible coatings (ECs) can be used as carriers of LAB and could provide an alternative natural preservation method. The effectiveness of Lactobacillus plantarum against fungal decay on grapes applied together with EC was studied. Different formulations with or without L. plantarum were considered, using pregelatinized potato starch (PS) or sodium caseinate (NaC) as main components of the coating matrices. In some of the formulations, oleic acid (OA) was added as a surfactant. The population dynamics of the bacterium and its ability to control fungal decay were studied together with the assessment of fruit quality. NaC-based formulations improved survival of L. plantarumon fruit surface after 7 days of storage in comparison with a water control. On the other hand, L. plantarum in PS-based formulation without OA reduced Botrytis incidence more than when applied in NaC formulation or in water. Coatings had little effect on berry quality (weight, color, firmness, and soluble solids content) of grapes throughout storage, although some of the coated samples maintained acidity and maturity index during storage better than others. Therefore, LAB applied in ECs could provide a viable biocontrol method for postharvest disease in grapes. [ABSTRACT FROM AUTHOR]

A 3-year study was undertaken to establish the effect of field nutritional sprays, combined with insecticide treatments or not against Asian Citrus psyllid, on the fruit quality of 'Valencia' orange trees affected by the greening disease Huanglongbing (HLB). Four replicated plots were harvested, juiced, and pasteurized. Nine to twelve trained panelists evaluated the juice using seven flavor, five taste, four mouthfeel and three aftertaste descriptors. There was little difference between treatments in 2013; only orange peel flavor and bitterness were significantly lower for the insecticide treatment. In 2014, positive attributes, such as orange and fruity flavor, sweetness and mouthfeel body, were significantly higher in the insecticide treatment. Sourness was highest in untreated control, and there were no differences between treatments for bitterness. In 2015, negative attributes, such as grapefruit, orange peel and typical HLB flavor, sourness, bitterness, and astringency, were significantly higher in untreated control fruit, suggesting perhaps that the beneficial effect of nutritional and insecticide treatments was cumulative, only manifesting on the 3rd year of the study, and or because of the progression of the disease affecting untreated controls. Data are discussed in relation to juice chemical composition, including volatiles, sugars, acids, limonoids, and flavonoids, adding to the fundamental knowledge concerning chemical drivers of orange flavor. [ABSTRACT FROM AUTHOR]

Background: Although many of the volatile constituents of flavor and aroma in citrus have been identified, the knowledge of molecular mechanisms and regulation of volatile production are very limited. Our aim was to understand mechanisms of flavor volatile production and regulation in mandarin fruit. Result: Fruits of two mandarin hybrids, Temple and Murcott with contrasting volatile and non- volatile profiles, were collected at three developmental stages. A combination of methods, including the isobaric tags for relative and absolute quantification (iTRAQ), quantitative real-time polymerase chain reaction, gas chromatography, and high-performance liquid chromatography, was used to identify proteins, measure gene expression levels, volatiles, sugars, organic acids and carotenoids. Two thirds of differentially expressed proteins were identified in the pathways of glycolysis, citric acid cycle, amino acid, sugar and starch metabolism. An enzyme encoding valencene synthase gene (Cstps1) was more abundant in Temple than in Murcott. Valencene accounted for 9.4% of total volatile content in Temple, whereas no valencene was detected in Murcott fruit. Murcott expression of Cstps1 is severely reduced. Conclusion: We showed that the diversion of valencene and other sesquiterpenes into the terpenoid pathway together with high production of apocarotenoid volatiles might have resulted in the lower concentration of carotenoids in Temple fruit. [ABSTRACT FROM AUTHOR]

BACKGROUND Fruit texture is a primary selection trait in southern highbush blueberry ( SHB) breeding to increase fresh fruit postharvest quality and consumer acceptance. A novel crisp fruit texture has recently been identified among SHB germplasm. In this study, we developed a common set of descriptors that align sensory evaluation of blueberry fruit texture with instrumental measures that could be used for quantitative measurements during pre- and postharvest evaluation. RESULTS Sensory and instrumental characteristics were measured in 36 and 49 genotypes in 2010 and 2011, respectively. A trained sensory panel evaluated fresh fruit based on five common textural attributes in 2010 and 2011: bursting energy, flesh firmness, skin toughness, juiciness and mealiness. Instrumental measures of compression and bioyield forces were significantly different among cultivars and correlated with sensory scores for bursting energy, flesh firmness and skin toughness ( R > 0.7, except skin toughness in 2011), but correlations with sensory scores for juiciness and mealiness were low ( R < 0.4). CONCLUSION The results of sensory and instrumental measures supported the use of both compression and bioyield force measures in distinguishing crisp from standard-texture genotypes, and suggest that crisp texture in SHB is related to the sensory perception of bursting energy, flesh firmness and skin toughness. © 2014 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Limonin and nomilin are two bitter compounds present in citrus and are thought to cause off-flavor in Huanglongbing ( HLB)-infected fruit/juice. This study determined the best estimate thresholds of limonin, nomilin and their combination in matrices composed of sugars and acids at levels found in orange juice, and in orange juice, using the three-alternate forced-choice methodology. Further, the effect of sucrose or citric acid in orange juice on the bitterness perception of both compounds was investigated. In a simple matrix (sucrose and citric acid), the threshold of limonin was 4.0 mg/ L, lower than the threshold of nomilin, which was 5.4 mg/ L. Together in a 1:1 ratio, limonin and nomilin acted synergistically and both thresholds decreased. When adding nomilin at a fixed subthreshold concentration of 2 mg/ L, limonin threshold decreased to 2.6 mg/ L. Recognition thresholds in orange juice were 4.7 and 2.6 mg/ L for limonin and nomilin, respectively. Added sucrose, but not citric acid, decreased the perception of bitterness induced by limonin and nomilin in orange juice. Practical Applications Florida orange juice processors are encountering increased juice bitterness resulting from elevated levels of the bitter compounds limonin and nomilin due to citrus greening or Huanglongbing disease ( HLB). Increased knowledge of sensory perception of limonin and nomilin in orange juice will help processors determine the final quality of juice made with fruit from groves infected with HLB. In a model solution, nomilin decreased the perception threshold of limonin. In orange juice, recognition thresholds were 4.7 and 2.6 mg/ L for limonin and nomilin, respectively, suggesting that orange juice containing such levels of these two compounds would taste bitter. As sucrose decreased bitterness perception of juice spiked with limonin and nomilin, blending with juice having higher sugar levels could be used for bitter off-flavor management for juice made with fruit strongly affected by the disease. [ABSTRACT FROM AUTHOR]

The strawberry breeding program of the University of Florida develops varieties that are highly adapted to west-central Florida, where approximately 8,800 acres of strawberries were grown during the 2009–10 season. In order to gain insight into breeding progress over time, two advanced selections and ten released cultivars, from Florida Belle (1975) to Florida Radiance (2008), were compared for various fruit quality traits. Cultivars and selections were arranged in a randomized complete block design at each of two locations (Balm, FL and Dover, FL). Fruit size varied dramatically with a minimum average weight of 16.2 g for ‘Dover’ (1979) and a maximum of 30.8 g for ‘Elyana’ (2008). Regression of average fruit weight on year of release showed an average gain in fruit size of 0.26 g/yr (R2 = 0.44). Improvements in fruit uniformity were also apparent, but gains for internal flesh color were not sustained. There was wide seasonal variability in sugars (sucrose, glucose, fructose, Brix) and acids (citric, malic, and titratable acidity); March tended to produce fruit with lower sugars. Sugars were highest in February while acids were highest in January. Also, correlations were found between sugars and volatiles having fruity and strawberry characters. Comparison of chemical data with sensory data from related studies indicates that instrumental measures, particularly for SSC/TA, could aid in breeding for improved flavor. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to evaluate the use of an ethanol vapor release pad and a saprophytic yeast Cryptococcus infirmo-miniatum (CIM) to reduce decay and maintain postharvest quality of intact or fresh-cut sweet cherries (Prunus avium) cv. Lapins and Bing. Intact or fresh-cut fruit were packed in perforated clamshells (capacity 454g) and stored at 1, 10 or 20°C for up to 21, 14 and 8d, respectively. For ethanol treatment, a pad made with silica gel powder containing 10g ethanol and covered with perforated film, which allows ethanol vapor to diffuse gradually, was attached to the upper lid of the clamshells. Ethanol treatment caused accumulation of ethanol in the packaging headspace, about 10μLL−1 with little change within 14d at 1°C, 23μLL−1 at d 1 and decreased to 15μLL−1 at d 10 at 10°C, and 26μLL−1 at d 1 and decreased to 13μLL−1 at d 3 at 20°C. Ethanol content in fruit was less than 9mgkg−1 in all the control fruit, and increased to 16, 34 and 43mgkg−1 in ethanol-treated fruit at 1, 10 and 20°C, respectively. Nonetheless, a sensory taste panel did not perceive any flavor difference from the ethanol treatment. The ethanol treatment retarded softening, darkening, and acid decrease in fruit as well as discoloration of the stems, and extended shelf-life of intact cherries. Ethanol reduced brown rot (Monilinia fructicola) in fresh-cut cherries stored at 20°C, but not at 1 and 10°C. A pre-packaging dip in CIM completely controlled brown rot in inoculated fresh-cut cherries stored at 1°C, and in naturally infected cherries at 20°C. [Copyright &y& Elsevier]

Some anecdotal reports suggest that infection of citrus trees with Candidatus Liberibacter asiaticus (Las), the suspected causal agent of huanglongbing (HLB) disease, imparts off flavor to orange juice. It is of interest to the industry to know how Las infection affects juice quality with respect to cultivar, maturity, or processing method. Hamlin, Midsweet, and Valencia oranges were harvested over 2 y from trees that tested negative (Las−) or positive (Las+) for Las from different groves and included normal looking (nonsymptomatic) and symptomatic fruit (small, green, and lopsided) from Las+ trees. In the 1st year, fruit were manually juiced, while in the 2nd year, a commercial process was used. Juice from Las+ trees was compared to juice from Las− trees in difference-from-control tests, and by descriptive analysis. Results showed large variability due to tree, harvest date, and cultivar. Juice from Hamlin Las+ trees tended to be more bitter and sour than its Las− counterpart. In contrast, hand processed Valencia juice from Las+ trees was perceived to have some off-flavor and bitterness compared to control, but the following year, commercially processed Valencia juice from Las+ trees was perceived to be only slightly more sour than juice from Las− trees for the April harvest, and to be sweeter for the June harvest. When juice from individual replicates was pooled to be more representative of a commercial situation, there was no difference between Las+ and Las− juice in Valencia. Trained panel differences were noted for juice from Hamlin Las+ fruit, especially for symptomatic fruit. Practical Application: Assumptions that juice made from oranges harvested from Huanglongbing (from infection with Liberibacter sp.) affected trees is off-flavored appeared to be generally more true for Hamlin juice than for Midsweet or Valencia, especially for Hamlin juice made from symptomatic fruit. For Midsweet and Valencia, flavor differences between juice made from fruit harvested from diseased or healthy trees varied greatly between trees, season, and even processing method. Under a commercial processing situation, where juice is blended from several varieties, seasons, and multiple locations, it is expected that off-flavor will not be a major problem. [ABSTRACT FROM AUTHOR]

Thresholds for flavour volatiles have been traditionally calculated in water or air but they may vary widely in more complex matrices such as milk, gels or fruit slurries. The data presented are part of a continuing study to provide the industry with threshold guidelines more adequate for the use of flavours in citrus juices. Thresholds of aroma compounds of orange juice (OJ) were determined in reconstituted pump-out (RPO), approaching a deodorized OJ matrix and served at 10-12 °C, the temperature at which OJ is consumed. The three-alternative forced choice (3-AFC) method was used (ASTM: E-679). Sixteen to twenty panelists were presented with RPO samples arranged in five rows of three samples corresponding to five spiking levels, each separated by a factor of 3, with a 3-AFC presentation at each level. For each compound, the test was repeated four times. Compounds tested were verified for purity by GC-MS and GC-O. Orthonasal and retronasal thresholds for esters were twice (methyl butanoate) to 30 times (ethyl propanoate) higher in the orange juice matrix than published values in water. The odour activity values (OAVs) of volatile compounds were calculated for two OJs; nine compounds had an orthonasal OAV < 1 when using thresholds determined in RPO, while in contrast, these compounds had an OAV > 1 when calculated with published thresholds determined in water. The relative OAV of some compounds had changed with respect to each other, indicating a different contribution of these compounds to OJ flavour when their OAV was calculated in RPO. These results show the importance of non-water-soluble compounds on odour and flavour perception. The threshold values provided herein are directly usable by the industry, in comparison with the current values published in water, and will help in developing models that would explain OJ flavour based on interactions with the matrix. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Mango fruit (Mangifera indica L.), cv. ‘Cogshall’, ‘Kent’ and ‘Keitt’ were harvested at different maturities (61–115d past flowering and 80–307averageg fresh weight for ‘Cogshall’) and at different sizes (364–1563 and 276–894averageg fresh weight for ‘Keitt’ and ‘Kent’, respectively). Immediately after harvest (green) or after 1 week of ripening at room temperature (ripe), fruit were homogenized or left intact and evaluated by electronic nose (enose) or by gas chromatography (GC) for aroma and other volatiles as well as for soluble solids and acids. Volatile data from the different harvest maturities and ripening stages were discriminated by using multivariate statistics (discriminant factor analysis). Both the enose and GC were able, in most cases, to separate fruit from different harvest maturities, especially for ‘Cogshall’ mangoes, at both the green and ripe stages as well as discriminate green from ripe fruit and fruit from the different varieties within a maturity stage. Solids and acids data indicated that later harvest maturities resulted in sweeter fruit and later-harvested fruit had a different volatile profile from earlier-harvested fruit. Mango fruit volatiles may be useful as maturity markers to determine optimal harvest maturity for mango fruit that results in full quality upon ripening. [Copyright &y& Elsevier]

Organic foods are produced using agricultural practices that emphasize renewable resources and conservation of soil and water. Horticultural crops are grown and processed without synthetic fertilizers, pesticides, ingredients and processing aids. Crops or ingredients derived from genetic engineering, and use of ionizing radiation are prohibited in organic production. The challenge is to deliver produce that has the same safety, quality and shelf life as conventional products, with a limited array of tools available for sanitation and postharvest treatments. Organic operators, professionals servicing the industry, us well as researchers involved in organic production practices, should be aware of all the points in the process of storing, handling and transforming horticultural crops where accidental contamination could occur, and thus compromise organic integrity. This presentation summarizes the major points of the National Organic Program for processing and handling, and gives suggestions for postharvest research. For example, finding organic alternatives for postharvest decay control is critical to maintain food safety. Additionally, ingredients compatible for fresh cut and produce coatings must be developed for the organic market for food safety and competitiveness. [ABSTRACT FROM AUTHOR]

Thresholds for flavour volatiles have been traditionally calculated in water or air, but they may vary widely in more complex matrices. Thresholds of key aroma compounds of orange juice (OJ) were determined in a deodorized OJ matrix. The three-alternative-forced-choice (3-AFC) method was used (ASTM: E-679). Untrained panelists, 33-58 in number, were presented with deodorized orange juice samples arranged in five rows of three samples, corresponding to five spiking levels, each separated by a factor of 3, with a 3-AFC presentation at each level. The test was repeated at least three times for experienced panelists. Odour thresholds in the orange juice matrix were 15 times (citral, hexanal) to over 200 times ( β-pinene, limonene) higher than published values in water. Retronasal odour thresholds were more consistent with published values, being higher only by 2-60-fold, except for octanal which was higher by 187-fold. These results will provide the industry with more realistic threshold guidelines for use in flavouring citrus juices. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

• 21 papaya accessions were evaluated, including large-fruited and solo types. • Yield, fruit size, soluble solids, and titratable acidity varied among accessions. • 124 volatiles were detected, and 25 had odor activity by GC-O. • A few papaya accessions have potential for commercial production in Florida. Papaya (Carica papaya L.) is a globally popular tropical fruit that can either be used in an unripe, "mature green" state in savory dishes, or consumed when ripe and sweet. In recent years, commercial papaya growers in southern Florida have favored large-fruited accessions often destined for the mature green market. Increased cultivation of papayas for the dessert fruit market, especially varieties with superior fruit quality may facilitate growth of the industry. Therefore, a study was designed to identify varieties that perform well in southern Florida, as well as accessions possessing useful characteristics for future breeding work. A total of 21 papaya accessions were assessed for yield components, plant height, and ripe fruit quality traits with an emphasis on aroma. In general, small fruited solo-type papayas were among the tallest accessions at first harvest reaching up to 244 cm tall for 'Kapoho #1' and with first fruit insertion heights up to 152 cm for 'Kapoho #2'. N08–75, 'Sunrise #2', and 'Sunset' had higher average fruit numbers (43, 45, and 37 fruit per plant, respectively) than some of the larger fruited accessions like Saipan Red #1 (7 fruit per plant) throughout a six-month harvest period. The accessions with the highest fruit weights ranged from 1.48 to 2.13 kg for Brash Panama, HAES 7836, N07–24, Saipan Red #1, and Saipan Red #2. There were significant differences among the accessions for fruit quality traits including pH (4.55–5.13), titratable acidity (0.10–0.23%), and total soluble solids (8.9–14.5%). Quantification of 112 putatively identified and 12 unknown volatile compounds revealed terpenes as the most abundant components in 18 accessions, with linalool typically at the highest concentration. Gas chromatography-olfactometry (GC-O) revealed 26 volatiles that may contribute to aroma. Several of these compounds including butanoic acid, methyl butanoate, octanoic acid, and (E)-citral varied greatly in abundance among accessions. The variability observed for important fruit quality and agronomic traits suggests potential for improvement through plant breeding, as well as expanded cultivation of currently available varieties for the dessert fruit market in southern Florida. [ABSTRACT FROM AUTHOR]

Fruit quality is of increasing importance for consumers but is a complex trait for growers, as it is affected by environment, genotype, and crop management interactions. Decision support tools, such as computer models that simulate crop growth and development can help optimize production but require further improvement to simulate quality aspects. The goal of this study was to apply the newly developed CROPGRO-Strawberry model in the Decision Support System for Agrotechnology Transfer (DSSAT) model framework and develop a module for the dynamic prediction of quality traits for strawberry. Experimental data from Florida with quality measurements from multiple harvests were correlated with indices based on preharvest weather conditions (temperature, radiation, rainfall) and simulated model parameters (evapotranspiration) during fruit development. Two quality relationships based on linear equations were identified and integrated into the model to simulate strawberry fruit soluble solids content (r ² 5 0.89, d 5 0.97) and titratable acidity (r ² 5 0.55, d 5 0.85) based on preharvest temperature. A strategic analysis with historical weather data for a subtropical growing region over a 10-year period showed the importance of seasonal climate variability for simulated strawberry yield and fruit quality across different harvest months. The improved CROPGRO-Strawberry model is the first process-based crop model to predict selected quality traits across multiple harvests throughout the season and can be extended to other crop models for which quality traits are important [ABSTRACT FROM AUTHOR]

• A large variation in total oil content was found among14 avocado genotypes. • Oleate, palmitate and linoleate were the major fatty acid components in all genotypes. • Acetaldehyde, C-6 aldehydes and mono/sesquiterpenes were the major VOCs. • '35707' and 'PA-6206' were rich in total oil content and unsaturated fatty acids. Worldwide avocado consumption is growing due to potential health benefits. Most research has been focused on 'Hass', which does not perform well in Florida. Fatty acids and volatile organic compounds (VOCs) were evaluated in 14 avocado genotypes grown in East-Central Florida conditions and compared to 'Hass'. Two saturated and five unsaturated fatty acids were detected. Total oil content (TOC) was 11–25%, with 58.2–71.5% unsaturated fatty acids (UFA). 'FL Hass' contained 20% TOC, near the average for genotypes tested, but with a low UFA of 61.9%. 'PA-6206' (a 'Hass' x 'Bacon' seedling) and '35707' (a 'Catalina' seedling) had higher TOC and UFA than other genotypes, while the mostly West Indian types such as 'Simmonds', 'Day', 'Pflume' and 'Miguel' had low TOC. Detected VOCs were acetaldehyde, hexanal, (E)-2-hexenal, limonene, α-cubebene, α-copaene, and β -caryophyllene. Most genotypes contained most of the VOCs. 'Monroe' lacked C6 aldehydes, and 'Pflume', 'Bernecker-43', 'Lula' and '35707' lacked some or all sesquiterpenes. [ABSTRACT FROM AUTHOR]

Sweet orange (Citrus sinensis) exhibits limited genetic diversity and high susceptibility to Huanglongbing (HLB). Breeding HLB-tolerant orange-like hybrids is in dire need. However, our understanding of the key compounds responsible for orange flavor and their genetic regulation remains elusive. Evaluating 179 juice samples, including oranges, mandarins, Poncirus trifoliata, and hybrids, distinct volatile compositions were found. A random forest model predicted untrained samples with 78% accuracy and identified 26 compounds crucial for orange flavor. Notably, seven esters differentiated orange from mandarin flavor. Cluster analysis showed six esters with shared genetic control. Differential gene expression analysis identified C. sinensis alcohol acyltransferase 1 (CsAAT1) responsible for ester production in orange. Its activity was validated through overexpression assays. Phylogeny revealed the functional allele was inherited from pummelo. A SNP-based DNA marker in the coding region accurately predicted phenotypes. This study enhances our understanding of orange flavor compounds and their biosynthetic pathways and expands breeding options for orange-like cultivars.k [ABSTRACT FROM AUTHOR]

Abstract Two major winter melon ( Benincasa hispida ) cultivars, waxy ‘Large Round’ and non-waxy ‘Southern Dark Skin’ were used for comparison of the physical, chemical and sensory properties of processed juice. Two types of juice were processed by using non-waxy fruits: non-waxy juice without peel (NW) and non-waxy juice with peel (NWP). For waxy fruit, the juice was prepared without peel (W) only. Peel tissues contributed firm particles, and more primary and secondary metabolites. The total tyrosine, phenylalanine, and dietary fiber content in NWP were 12.14 mg L−1, 11.78 mg L−1 and 1.04% respectively, which were significantly higher than in W and NW. However, NWP had more off-flavor, such as hexanal and ( E )-2-hexenal, less stability, and higher pulpy mouthfeel. W samples were more stable than NW and NWP during storage without visible sedimentation. The glucose, fructose and TA content of W were 0.58%, 0.58 and 0.23% respectively, which were significantly lower than in NW and NWP. The W juice also had less dimethyl disulfide, and hexanal, and was better rated by the sensory panel for having lower sour, salty, bitter, grassy and cooked vegetable characteristics. The results indicate that the waxy ‘Large Round’ melons are a viable candidate for juice processing. Highlights • Compared to non-waxy winter melons, waxy fruits possess better processing property. • Juice from waxy winter melons is physically stable without visible sedimentation. • Juice from waxy winter melons has less sugar, acid and off-flavor. • Juice from waxy winter melons has better sensory properties. • Fruit peels contribute more amino acids, but cause off-flavor and pulpy mouthfeel. [ABSTRACT FROM AUTHOR]

'Valencia' orange trees from groves with 90% infection by Candidatus liberibacter asiaticus (CLas), the presumed pathogen for citrus greening or huanglongbing (HLB) disease, were treated with insecticide (I), a nutritional spray (N), and insecticide plus nutritional spray (I + N). Controls (C) were not treated. Fruit were harvested in March to April, 2013, 2014, and 2015, juiced, and the juice was frozen for later chemical analyses. Titratable acidity (TA), soluble solids content (SSC), SSC/TA ratio, many volatiles, flavonoids, and limonoids showed differences because of season, whereas SSC, several volatiles (ethanol, cis-3 hexenol, α-terpinene, ethyl acetate, and acetone), flavonoids (narirutin, vicenin-2, diosmin, nobiletin, heptamethoxy flavone), and limonoids (nomilin and nomilinic acid glucoside) showed differences because of treatment. However, consistent patterns for chemical differences among seasons were not detected. TA tended to be higher in N and C the first two seasons and SSC/TA higher in I and I + N for all seasons (not significant for 2014). Bitter limonoids tended to be higher in I, N or I + N over the seasons. Principal Component Analysis showed that there was a good separation by season overall and for treatment in 2013. In 2014 and 2015, the insecticide treatments (either I or I + N) had the highest sugar and SSC/TA levels and lowest TA levels, although not always significant, as well as higher juice CLas cycle threshold (Ct) levels, indicating lower levels of the pathogen. [ABSTRACT FROM AUTHOR]

BACKGROUND Winter melon ( Benincasa hispida) is a widely consumed crop in Asia, and believed to impart special benefits to human health. The nutritional composition and sensory properties of four juice types, resulting from a combination of pulp levels (low/high pulp, LP/ HP) and thermal processing (with/without boiling, B/ NB), LPNB, HPNB, LPB and HPB, were compared. RESULTS The juices had low sugars (< 20 g kg−1) and low titratable acidity (about 2 g kg−1). The insoluble solids, glucose, fructose and citric acid content in LP juice were significantly lower than in HP juice. The phenolic amino acids phenylalanine, tyrosine, and tryptophan were detected at 10-45 mg L−1 levels, and the antioxidant activity ranged from 36 to 49 mg gallic acid L−1. C6 and C9 aldehydes were mainly found in HP juice, and boiling induced the accumulation of sulfur compounds and C5 aldehydes. The LPNB juice showed the highest acceptability in the sensory panel. The frozen concentrated orange juice ( FCOJ) reconstituted with LPNB was preferable to regular FCOJ for 31% of panelists and not different for 20% of panelists. CONCLUSION The low sugar/low acid LPNB juice with 'fresh' flavor could be developed to replace water for reconstituting FCOJ with enhanced nutritional value. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Hybrids of Poncirus trifoliata L. Raf. with Citrus have shown degrees of tolerance to the deadly citrus greening disease, hence prompting interest as potential commercial varieties. Although P. trifoliata is known to produce fruit that is inedible, fruit from many advanced hybrid trees have not been evaluated for their quality potential. The sensory quality of selected Citrus hybrids with varying degrees of P. trifoliata in their pedigrees is reported herein. Four Citrus × P. trifoliata hybrids developed through the USDA Citrus scion breeding program—1‐76‐100, 1‐77‐105, 5‐18‐24, and 5‐18‐31—had acceptable eating quality and sweet and sour taste, with mandarin, orange, fruity–noncitrus, and floral flavors. On the other hand, hybrids with higher proportion of P. trifoliata in their pedigrees, US 119 and 6‐23‐20, produced a juice characterized by green, cooked, bitter, and Poncirus‐like flavor and aftertaste. Partial least square regressions revealed that the Poncirus‐like off‐flavor is likely due to a combination of higher than typical amounts of sesquiterpene hydrocarbons (woody/green odor), monoterpenes (citrus/pine), and terpene esters (floral) and a lack of aldehydes with typical citrus odor (octanal, nonanal, and decanal). Sweetness and sourness were mostly explained by high sugars and acids, respectively. Further, carvones and linalool contributed to sweetness in the samples from early and late seasons, respectively. In addition to highlighting chemical contributors to sensory descriptors in Citrus × P. trifoliata hybrids, this study provides useful information on sensory quality for future citrus breeding efforts. Practical Application: The relationships between the sensory quality and secondary metabolites of Citrus × P. trifoliata hybrids described in this study help identify disease‐resistant Citrus scion hybrids with acceptable flavor and help mobilize this resistance in future breeding efforts. It also shows potential of such hybrids to be commercialized. [ABSTRACT FROM AUTHOR]

The article informs about different forms of Fragaria chiloensis cultivated by native individuals in South America also known as White-fruited strawberries. Topics include Newer cultivars with fruit sizes similar to that of red strawberries that have recently emerged as high-value products in Asia; and existing pineberry cultivars are not suitable for commercial production in Florida.

In an earlier study, an electronic tongue system (e-tongue) has been used to differentiate between orange juice made from healthy fruit and from fruit affected by the citrus greening or Huanglongbing (HLB) disease. This study investigated the reaction of an e-tongue system to the main chemicals in orange juice that impact flavor and health benefits and are also impacted by HLB. Orange juice was spiked with sucrose (0.2-5.0 g/100 mL), citric acid (0.1%-3.0% g/100 mL) and potassium chloride (0.1-3.0 g/100 mL) as well as the secondary metabolites nomilin (1-30 μg/mL), limonin (1-30 μg/mL), limonin glucoside (30-200 μg/mL), hesperidin (30-400 μg/mL) and hesperetin (30-400 μg/mL). Performance of Alpha MOS sensor sets #1 (pharmaceutical) and #5 (food) were compared for the same samples, with sensor set #1 generally giving better separation than sensor set #5 for sucrose, sensor set #5 giving better separation for nomilin and limonin, both sets being efficient at separating citric acid, potassium chloride, hesperitin and limonin glucoside, and neither set discriminating hesperidin efficiently. Orange juice made from fruit over the harvest season and from fruit harvested from healthy or HLB-affected trees were separated by harvest maturity, disease state and disease severity. [ABSTRACT FROM AUTHOR]

Tomato fruits exposed to chilling temperatures suffer aroma loss prior to visual chilling injury (CI) symptoms. Methyl salicylate (MeSA) and methyl jasmonate (MeJA) treatments were reported to alleviate the development of visual CI; however, it is unknown if the treatments alleviate internal CI in the form of aroma loss. In this research, ‘FL 47’ tomatoes at breaker stage were treated with MeSA or MeJA vapor prior exposure to chilling temperature. The chilling treatment did not result in visual CI; however, for internal CI it generally suppressed production of oxygen-containing heterocyclic compounds, ketones, sulfur- and nitrogen-containing heterocyclic compounds, alcohols, and aldehydes, including 13 important aroma contributors to tomato fruit. MeJA had no impact on sensory evaluation in spite of resulting in slightly altered volatile profile; however, MeSA alleviated the CI-induced reduction of a number of volatile compounds, and thereby enhanced tomato aroma. [ABSTRACT FROM AUTHOR]

Huanglongbing, or citrus greening disease, progressively damages and ultimately kills citrus trees. While this disease does not affect human health, it is associated with bitter off-flavor for orange juice. The objective of this study was to determine the level of HLB-symptomatic (HLBs) juice (made from fruit symptomatic for the disease, harvested from diseased trees) that can be added to healthy juice (extracted from fruit harvested from healthy trees) so that the off-flavor associated with such juice is not perceived. Varying amounts of Hamlin or Valencia HLBs orange juices were blended with respective healthy juices to make 6.25, 12.5, 25, and 50 mL HLBs/100 mL blends. Chemical and sensorial differences were found for both varieties. HLBs juice had lower soluble solids but higher acidity, and limonin and nomilin levels than healthy juice. However, only about 27% of the panelists were able to recognize taste differences in 25 mL HLBS/100 mL blend and less than 9% could recognize taste differences with 6.25 and 12.5 mL HLBs/100 mL blends. Electronic tongue differentiation of blends supported the chemical and sensory differences. Results showed that adding small amounts of HLBs juice to healthy juice does not compromise taste quality. [ABSTRACT FROM AUTHOR]

Background: There is interest in improving the flavor of commercial strawberry (Fragaria × ananassa) varieties. Fruit flavor is shaped by combinations of sugars, acids and volatile compounds. Many efforts seek to use genomics-based strategies to identify genes controlling flavor, and then designing durable molecular markers to follow these genes in breeding populations. In this report, fruit from two cultivars, varying for presence-absence of volatile compounds, along with segregating progeny, were analyzed using GC/MS and RNAseq. Expression data were bulked in silico according to presence/absence of a given volatile compound, in this case γ-decalactone, a compound conferring a peach flavor note to fruits. Results: Computationally sorting reads in segregating progeny based on γ-decalactone presence eliminated transcripts not directly relevant to the volatile, revealing transcripts possibly imparting quantitative contributions. One candidate encodes an omega-6 fatty acid desaturase, an enzyme known to participate in lactone production in fungi, noted here as FaFAD1. This candidate was induced by ripening, was detected in certain harvests, and correlated with γ-decalactone presence. The FaFAD1 gene is present in every genotype where γ-decalactone has been detected, and it was invariably missing in non-producers. A functional, PCR-based molecular marker was developed that cosegregates with the phenotype in F1 and BC1 populations, as well as in many other cultivars and wild Fragaria accessions. Conclusions: Genetic, genomic and analytical chemistry techniques were combined to identify FaFAD1, a gene likely controlling a key flavor volatile in strawberry. The same data may now be re-sorted based on presence/absence of any other volatile to identify other flavor-affecting candidates, leading to rapid generation of gene-specific markers. [ABSTRACT FROM AUTHOR]

BACKGROUND: Fresh orange juice is perceived to be more wholesome than processed juice. Fresh juice may have flavor and nutrients that differ from pasteurized or processed juice. RESULTS: 'Hamlin' and 'Valencia' oranges were extracted using a commercial food service juicer, pasteurized or not, resulting in fresh-commercial juice (FCJ) or pasteurized juice (FCPJ) for comparison with pasteurized processed juice (PPJ) in 2009, and gently hand-squeezed 'Valencia' juice (HSJ) in 2010 for quality attributes. There was higher peel oil, lower pectin content, and less cloud loss in FCJ/FCPJ compared to PPJ and HSJ regardless of pasteurization. Titratable acidity was generally higher and the ratio of solids to acids lower in FCJ/FCPJ or HSJ compared to PPJ. FCJ/FCPJ had generally higher levels of most aroma volatiles than did PPJ and, overall, the highest esters and terpenes, while methanol and ethanol levels were highest in HSJ. For sensory evaluation, FCJ/FCPJ had more peel oil and PPJ more cooked flavor than other samples, while 'Valencia' HSJ was preferred over the other juices. CONCLUSION: High peel oil content and thermo-pasteurization process decreased cloud loss of orange juice. Extraction and finishing processes rather than pasteurization or oil content were major factors in influencing orange juice flavor quality. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The electronic nose (e-nose) is designed to crudely mimic the mammalian nose in that most contain sensors that non-selectively interact with odor molecules to produce some sort of signal that is then sent to a computer that uses multivariate statistics to determine patterns in the data. This pattern recognition is used to determine that one sample is similar or different from another based on headspace volatiles. There are different types of e-nose sensors including organic polymers, metal oxides, quartz crystal microbalance and even gas-chromatography (GC) or combined with mass spectroscopy(MS) can be used in a non-selective manner using chemical mass or patterns from a short GC column as an e-nose or "Z" nose. The electronic tongue reacts similarly to non-volatile compounds in a liquid. This review will concentrate on applications of e-nose and e-tongue technology for edible products and pharmaceutical uses. [ABSTRACT FROM AUTHOR]

Oranges can be satisfactorily processed for fresh slices using a process of enzyme infiltration under vacuum. Scored 'Valencia' and 'Hamlin' oranges were placed under 90 kPa vacuum in water, 1% citric acid (CA), or 1000 ppm pectinase (Ultrazym) at 30 °C for 2 min followed by 30 min incubation in air. After peeling, fruit were washed, cut, and all but CA-infused slices were dipped in water or 1% CA for 2 min. Drained slices were placed in sealed 454-mL deli containers and stored at 5 °C for up to 21 days. All 'Valencia' slices had microbial counts less than 1.0 log cfuµg-1 (cfu = colony-forming units) after 7 days storage, and slices from CA-infused fruit had less than 1.0 log cfu·g-1 after 21 days storage. For 'Hamlin', CA dips controlled bacterial growth on slices from water-infused oranges, except at 14 days. Enzyme-infused oranges resulted in slices with lower counts for both cultivars. CA-treated sliced (post enzyme treatment or by infusion) oranges had higher titratable acidity initially ('Hamlin') and after 14 days ('Valencia'). When presented to a taste panel, 'Valencia' slices from enzyme-peeled fruit were preferred for texture after 2 days and 8 days in storage, in contrast, slices from fruit infused with water or citric acid were least preferred, were firmer, and had thicker segment membranes. Appearance of enzyme-treated fruit was preferred for 'Hamlin' oranges. Enzyme treatments increased levels of aroma volatiles, methanol and methyl butanoate, in 'Hamlin' slices, but overall sensory flavor data were unaffected. [ABSTRACT FROM AUTHOR]

An herbaceous/grassy-like flavor has been reported by Chilean producers of Regina sweet cherry. There are no previous academic reports related to this flavor occurrence. Sweet cherries from five phenological stages were collected from six orchards with high herbaceous flavor incidence spanning Chilean production zones during the 2019/2020 season. Four experienced panelists tasted the fruit to identify the off-flavor incidence and intensity from four phenological stages, and the same cherries were analyzed for volatile compounds. Thirty-nine volatiles were identified and semi-quantified using solid-phase microextraction (SPME) and GC-MS. The highest off-flavor incidence was found at the bright red (stage 3) and mahogany colors (stage 4). No single volatile explained the herbaceous flavor consistently among orchards. However, it appeared that the off-flavor was related to delayed ripening in cherries, with more C6 aldehydes and less esters. Furthermore, rainfall and the elevation of the orchard had a significant effect on the incidence of off-flavor. Preharvest practices that promote fruit ripening along with avoiding early harvests are recommended to reduce the incidence of herbaceous flavor in Regina. [ABSTRACT FROM AUTHOR]

BACKGROUND Reducing the negative effects of chilling injury (CI) in tomatoes after harvest is essential to ensure good quality and to minimize losses. CI is a postharvest disorder associated with the generation of reactive oxygen species (ROS) in the fruit. Therefore, antioxidant accumulation can counteract ROS, alleviating CI symptoms. In this sense, it has been confirmed that a brief hot‐water (HW) immersion promotes the synthesis of antioxidants. RESULTS: HW treatment at 52 °C for 5 min significantly reduced chilling‐associated decay, from 66.7% to 17.2% in breaker turning (BT) and from 55.8% to 9.8% in mature green (MG) 'BHN‐602' tomatoes stored at 5 °C for 2 weeks and from 26.7% to 6.7% in BT tomatoes stored at 5 °C for 1 week. Also, HW treatment significantly increased lycopene content by 17% in BT tomatoes stored at 5 °C for 2 weeks, as well as ascorbic acid by 11%, lipophilic phenolics by 18% and total phenolics by 6.5% in BT tomatoes stored at 12.5 °C for 1 week. Despite the increase of antioxidants, HW treatment did not enhance the sensory aromatic profile, color and antioxidant capacity. Interestingly, HW treatment reduced ripening time by 3 days in MG tomatoes stored at 5 °C for 2 weeks or at 12.5 °C for 1 week. CONCLUSION: HW treatment applied to MG or BT 'BHN‐602' tomatoes can alleviate the development of some CI symptoms, particularly decay, possibly by increasing antioxidants that scavenge ROS. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Mandarins (or tangerines) are mainly consumed as fresh fruits due to the ease of peeling and desirable flavor. Sweetness, acidity, and flavor of mandarin are the most important criteria for consumer preference. The objective of this study was to evaluate the effects of harvest date on sensory and chemical components of four mandarin cultivars (Murcott, 411, Temple, and 'LB8‐9' Sugar Belle®). Volatiles were extracted from the headspace of juice samples with solid phase microextraction (SPME) and analyzed using gas chromatography‐mass spectrometry (GC‐MS). The optimum harvest window for eating quality of 411 was late January to mid‐February (soluble solids content [SSC]/titratable acidity [TA]: 11.3 to 14.0), Sugar Belle® fruits were best tasted when harvested from mid‐ to end of January (SSC/TA: 14.1 to 16.1), and February was the best month for harvesting Murcott (SSC/TA: 13.10 to 18.0) and Temple (SSC/TA:10.3 to 12.50). Sensory perception of sweetness, ripeness, and juiciness increased as SSC/TA increased while sourness and bitterness decreased. Pumpkin flavor, an indicator of overripe fruit, was mainly noticed late in the season. Tangerine flavor tended to decrease, whereas fruity‐noncitrus flavor tended to increase with fruit maturity. Monoterpenes were the most abundant volatiles and tended to decrease with fruit maturity, whereas alcohols, esters, and aldehydes increase. Aldehydes, esters, and alcohols were positively correlated with sweetness, ripeness, juiciness, and fruity characteristics, and negatively with sourness and bitterness. On the other hand, monoterpenes were positively correlated with bitterness and tangerine flavor, and negatively correlated with sweetness and fruity‐noncitrus flavor. The highest number of esters was found in Temple, whereas Murcott and 411 were high in aldehydes. [ABSTRACT FROM AUTHOR]

"Florida Brilliance" Strawberry. Fragaria ×ananassa, fruit breeding, small fruit. [Extracted from the article]

Fragaria vesca is a diploid strawberry species that produces gourmet, aromatic fruits with only limited commercial production because of its relative obscurity. Most F. vesca research focuses on genetics and fruit aroma, but yield and fruit quality data across diploid accessions are lacking. Sixteen F. vesca accessions were grown in replicated field plots in southern Florida to measure field performance and fruit quality over multiple harvests during a single growing season. Accessions 'Reine des Vallees', 'Baron Solemacher', 'Fragolina di Bosco', and 'Reugen' all had significantly higher yield (115-140 g/plot/week) and fruit number (117-139 fruit/plot/week) compared with 'Bowlenzauber', 'Attila', 'Ali Baba', and 'Pineapple Crush' (31-57 g/plot/week and 32-60 fruit/plot/week) during peak production. Total average yield ranged from 240 g ('Pineapple Crush') to 1194 g ('Baron Solemacher') per plot of 10 plants. Fruit number and fruit yield were highly correlated (R² = 0.96) for all accessions, and there was no significant difference in fruit weight among accessions through the entire season. Total soluble solids ranged from 10.9 to 13.5 °Brix, and fructose, glucose, sucrose, and total sugars ranged from 15.3 to 22.1, 13.5 to 20.0, 0.1 to 2.7, and 29.7 to 42.5 mg/g, respectively, fresh weight. Acidity ranged from 1.00% to 1.18% citric acid and was not consistently significantly different among accessions over multiple harvests. Forty-two aroma compounds were putatively identified over three harvests for each accession and included mostly esters and ketones with a few alcohols, terpenes, and aldehydes. The majority of these compounds were similarly abundant over harvests and among accessions with a few exceptions, including methyl anthranilate. These results are the first in-depth study of yield and fruit quality for a large number of F. vesca accessions that could lead to increased cultivation of this species for local markets. [ABSTRACT FROM AUTHOR]

Guava ( Psidium guajava ) fruit are valued for their rich, tropical aroma, but fruit quality data are lacking for many important cultivars. Guava is native to warm-climate areas of the Americas and is grown commercially in southern Florida, USA. Varieties relevant to south Florida display a high level of morphological diversity, including fruit color and shape. Fruit are commercially available at either a mature green stage which are harvested prior to full aroma development, or as mature yellow fruit which possess a full aroma profile. We sampled 27 guava accessions growing at the University of Florida’s Tropical Research and Education Center for aroma at immature, mature green, and mature yellow fruit developmental stages. Variability in pulp pH (3–4.6) was not indicative of fruit maturity, but titratable acidity (0.17–3.6%) did decrease throughout fruit development. Aroma profiles showed significant differences among accessions. Some volatiles including hexanal, ( E )-caryophyllene, and ( E )-2-hexenal were common across guava accessions and were present at all developmental stages. Other compounds including ( Z )-3-hexenyl acetate, ethyl butanoate, and ethyl octanoate had the greatest abundance only at the mature yellow stage of fruit development. Limonene, ( E )-cadina-1,4-diene, and β-ionone were abundant in some accessions and not detected in others (21, 10, and 14 out of 27 accessions, respectively). This work describes the comparative diversity of guava fruit quality for a large number of accessions through fruit development for the first time. Furthermore, these fruit quality data could support future breeding work towards the genetic improvement of guava flavor. [ABSTRACT FROM AUTHOR]

Citrus greening disease, also known as Huanglongbing (HLB), compromises the quality of citrus fruit and juice, causing increased bitterness, metallic taste, astringency and a burning mouthfeel. The chemical basis responsible for these changes remains largely unknown other than the roles of the bitter limonoids, limonin and nomilin, and of flavonoids that may cause astringency. A combination of chemical and sensory analyses was used to identify bitter components in HBL-affected orange juice (HLBOJ), and compared with juice from healthy fruit. DNA analysis of the juice revealed that HLBOJ was well infected with the bacteria, with Ct value of 27 compared with 33 for the healthy juice. There were differences (at least P  < 0.05) in pH, titratable acidity (TA), soluble solids content (SSC), SSC/TA, total sugars, citric acid, secondary metabolites and sensory characteristics between healthy and HBLOJ, with, limonin and nomilin being 7.8 and 21.6 fold higher in HLBOJ than in healthy juice, respectively. Nonvolatile juice compounds were fractionated using fast centrifugal partition chromatography and semi preparative HPLC. Some fractions (7 out of 10) were described as bitter, but did not contain limonoids, polymethoxylated flavones or hesperidin, and, instead, were composed of hydroxycinnamates, suggesting these compounds might be involved with this sensory attribute. [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate whether an electronic tongue (e-tongue) could differentiate “taste” profiles of full ripe tomato fruit of different cultivars, harvest maturities, and exposure to refrigeration or blanching. The four cultivars included: two common commercial cultivars, ‘Tygress’ and ‘FL 47’, with round shape and firm texture; ‘Tasti-Lee’, a hybrid with high lycopene content due to the crimson gene for the premium tomato market; and ‘Cherokee Purple’, an heirloom cultivar that consistently ranked very high in taste tests. Commercially, tomatoes are often harvested at the mature green (MG) stage for the fresh fruit and food service markets, and traditional vine-ripe harvested tomatoes are generally sold directly at farmer’s markets. To assess the effect of harvest maturity on fruit flavor once the fruit are fully ripened, fruit were harvested at six maturities from MG to full red. ‘Tygress’, ‘FL 47’, and ‘Tasti-Lee’ fruit all had similar total soluble solids (TSS) and titratable acidity (TA) content regardless of harvest maturity. Nonetheless, ‘Cherokee Purple’ had much higher TSS and TA at all but the MG harvest stage. E-tongue tests not only confirmed the differences detected in TSS/TA data, but also differentiated between the three commercial cultivars, and six harvest maturities. Both refrigeration and blanching are common kitchen practices and they were tested on ‘Tasti-Lee’ fruit for which some changes in the taste profiles were found by e-tongue, especially for the refrigeration treatment. E-tongue sensors ZZ, JE, BB, HA, and JB data correlated to TSS and TA, with significantly high correlations with TSS. E-tongue profiles not only significantly related to TSS, but successfully predicted TSS. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Citrus fruit flavor is an important attribute prioritized in variety improvement. The present study compared juice volatiles compositions from 13 selected citrus genotypes, including six mandarins (Citrus reticulata), three sour oranges (Citrus aurantium), one blood orange (Citrus sinensis), one lime (Citrus limonia), one Clementine (Citrus clementina) and one satsuma (Citrus unshiu). RESULTS: Large differences were observed with respect to volatile compositions among the citrus genotypes. ‘Goutou’ sour orange contained the greatest number of volatile compounds and the largest volatile production level. ‘Ponkan’ mandarin had the smallest number of volatiles and ‘Owari’ satsuma yielded the lowest volatile production level. ‘Goutou’ sour orange and ‘Moro’ blood orange were clearly distinguished from other citrus genotypes based on the analysis of volatile compositions, even though they were assigned into one single group with two other sour oranges by the molecular marker profiles. CONCLUSIONS: The clustering analysis based on the aroma volatile compositions was able to differentiate mandarin varieties and natural sub‐groups, and was also supported by the molecular marker study. The gas chromatography–mass spectrometry analysis of citrus juice aroma volatiles can be used as a tool to distinguish citrus genotypes and assist in the assessment of future citrus breeding programs. The aroma volatile profiles of the different citrus genotypes and inter‐relationships detected among volatile compounds and among citrus genotypes will provide fundamental information on the development of marker‐assisted selection in citrus breeding. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The article focuses on the Florida Beauty strawberry, a variety from the collaborative breeding effort between the University of Florida and the Queensland Department of Agriculture and Fisheries. Topics discussed include the variety's origin which came from a 2012 cross made by the breeding program between the university and the department, its description, and yield performance.

Background: Methyl anthranilate (MA) contributes an attractive fruity note to the complex flavor and aroma of strawberry (Fragaria spp.), yet it is rare in modern cultivars. The genetic basis for its biosynthesis has not been elucidated. Understanding the specific genes required for its synthesis could allow the development of gene/allelespecific molecular markers to speed breeding of flavorful strawberries. Results: Ripe fruits from individuals in an F1 population resulting from a cross between a MA producer and a non-producer were examined using a bulk-segregant transcriptome approach. MA producer and non-producer transcriptomes were compared, revealing five candidate transcripts that strictly co-segregated with MA production. One candidate encodes an annotated methyltransferase. MA levels are lower when this transcript is suppressed with RNAi, and bacterial cultures expressing the protein produced MA in the presence of anthranilic acid. Frozen fruit powders reconstituted with anthranilic acid and a methyl donor produced MA only if the transcript was detected in the fruit powder. A DNA-based molecular marker was developed that segregates with the MA-producing gene variant. Conclusions: These analyses indicate that the methyltransferase, now noted ANTHRANILIC ACID METHYL TRANSFERASE (FanAAMT), mediates the ultimate step of MA production in cultivated strawberry. Identification of this gene and its associated molecular marker may hasten breeding efforts to introduce this important volatile into modern cultivars. [ABSTRACT FROM AUTHOR]

Background: Flavor is an important attribute of mandarin (Citrus reticulata Blanco), but flavor improvement via conventional breeding is very challenging largely due to the complexity of the flavor components and traits. Many aroma associated volatiles of citrus fruit have been identified, which are directly related to flavor, but knowledge of genetic linkages and relevant genes for these volatiles, along with applicable markers potentially for expeditious and economical marker-assisted selection (MAS), is very limited. The objective of this project was to identify single nucleotide polymorphism (SNP) markers associated with these volatile traits. Result: Aroma volatiles were investigated in two mandarin parents ('Fortune' and 'Murcott') and their 116 F1 progeny using gas chromatography mass spectrometry in 2012 and 2013. A total of 148 volatiles were detected, including one acid, 12 alcohols, 20 aldehydes, 14 esters, one furan, three aromatic hydrocarbons, 16 ketones, one phenol, 27 sesquiterpenes, 15 monoterpenes and 38 unknowns. A total of 206 quantitative trait loci (QTLs) were identified for 94 volatile compounds using genotyping data generated from a 1536-SNP Illumina GoldenGate assay. In detail, 25 of the QTLs were consistent over more than two harvest times. Forty-one QTLs were identified for 17 aroma active compounds that included 18 sesquiterpenes and were mapped onto four genomic regions. Fifty QTLs were for 14 monoterpenes and mapped onto five genomic regions. Candidate genes for some QTLs were also identified. A QTL interval for monoterpenes and sesquiterpenes on linkage group 2 contained four genes: geranyl diphosphate synthase 1, terpene synthase 3, terpene synthase 4, and terpene synthase 14. Conclusions: Some fruit aroma QTLs were identified and the candidate genes in the terpenoid biosynthetic pathway were found within the QTL intervals. These QTLs could lead to an efficient and feasible MAS approach to mandarin flavor improvement. [ABSTRACT FROM AUTHOR]

Avocado (Persea americana Mill.) is a high-value fruit that continues to increase in consumer demand. A population of 'Hass'-'Bacon' hybrids was planted at USDA-ARS, Fort Pierce, as part of a study to find selections with good horticultural and postharvest quality traits for Florida. Extensive phenotypic data on quality were collected over 3 years. Ten selections were identified in 2014 and 2015 with promising fruit quality and postharvest shelf life characteristics and were tested in sensory panels using store-bought 'Hass' as the standard. In general, the selections had fruit quality similar to commercial 'Hass'. Avocados that were most liked were described as creamy in texture with buttery and nutty flavor. Only one selection (R7T54 in 2014) and one store-bought control ('Hass' in 2015) were disliked, which was associated with greater firmness at the time of evaluation, likely relating to insufficient postharvest conditioning. Furthermore, CA 'Hass' commercial requirements for minimum dry matter (20.8%) were generally achieved by these selections under Florida conditions, ranging from 18.4% to 25.7%. This study identified 10 selections with composition and sensory quality similar to 'Hass' that are suitable for further testing and development in Florida. [ABSTRACT FROM AUTHOR]

The effect of controlled-release chlorine dioxide (ClO2) gas on the safety and quality of grapefruit was studied. The experiments were run under controlled chamber systems with inoculated fruit, and in boxed fruit under commercial conditions. For the inoculation test, fruit artificially inoculated with either Escherichia coli or Penicillium digitatum, or naturally inoculated Xanthomonas citri ssp. citri (Xcc) (fruits with citrus canker lesions), were incubated in a chamber containing a dose equivalent to 0-60 mg⋅L-1 of pure ClO2 as an antimicrobial agent. After 24 hours, the microbial population on treated grapefruit was significantly reduced compared with that of control fruit: a dosage of 5 mg⋅L-1 completely inhibit the growth of E. coli and P. digitatum, but a dosage of 60 mg⋅L-1 was needed to completely kill Xcc. For the simulated commercial experiment, fruit were harvested in late Oct. 2015 passed through a commercial packing line, and packed in 29 L citrus boxes. ClO2 packets were attached to the top lids with the following five treatments: fast-release, slow-release, slow/fast-release combination (each containing 14.5 mg⋅L-1 of pure ClO2), double dose fast-release (containing 29 mg⋅L-1 of ClO2), and control. After 6 weeks of storage at 10 °C (to simulate storage and transportation) + 1 week of storage at 20 °C (to simulate retail marketing), the fruit quality was evaluated. The slow-release treatment at standard dose exhibited the best antimicrobial activity, reducing total aerobic bacterial count and yeast/mold count by 0.95 and 0.94 log colony-forming units (cfu)/g of fruit, respectively, and maintained the best visual, sensory, and overall quality. However, the higher dosage treatments resulted in phytotoxicity as evidenced by peel browning. [ABSTRACT FROM AUTHOR]

Citrus greening or huanglonbing (HLB) is thought to be caused by Candidatus Liberibacter asiaticus ( C Las) and is devastating the citrus industry worldwide. One symptom of HLB disease is excessive pre-harvest fruit drop. Recently, higher incidence of Lasiodiplodia theobromae ( Diplodia ) was found in HLB-symptomatic orange calyx abscission zones (AZ-C) than in non-symptomatic fruit, and the infection was positively correlated with the reduction in fruit detachment force (FDF), suggesting that Diplodia infection may be involved in the HLB-related pre-harvest fruit drop. To verify the hypothesis, we conducted two experiments. Experiment 1 was conducted by shaking HLB-affected ‘Hamlin’ and ‘Valencia’ orange trees during the harvest season (twice for ‘Hamlin’ and once for ‘Valencia’). The fruit that dropped from trees upon shaking were collected (D), and the fruit retained on trees after shaking were harvested (R). Fruit ethylene production was measured, and the levels of Diplodia and C Las in AZ-C of D and R fruit were analyzed. The results revealed significantly higher levels of Diplodia in D compared with R fruit; and ethylene was produced from more than half of the D fruit but none of the R fruit. Ethylene production was positively correlated with Diplodia level in D fruit. In experiment 2, a preliminary trial on the effect of fungicide (Quadris Top) application on incidence of Diplodia infection and fruit drop was investigated. The experiment was conducted in a commercial grove with essentially 100% of the trees being HLB-symptomatic, and included five citrus cultivars (‘Early Gold’ orange, ‘Midsweet’ orange, ‘Murcott’ tangor, ‘Navel’ orange and ‘Ray Ruby’ grapefruit). Diplodia levels were lower and FDF significantly higher in fungicide-treated compared to non-treated ‘Early Gold’, ‘Midsweet’ and ‘Murcott’ fruit, and consequently, the fruit drop was reduced by 45%, 30% and 46% that of non-sprayed controls, respectively. For ‘Navel’ or ‘Ray Ruby’ fruit, there was no significant change between sprayed and non-sprayed controls in the level of Diplodia , FDF or fruit-drop. The results consistently showed a positive correlation between Diplodia infection and fruit drop in HLB-affected fruit, indicating the possible involvement of the fungus in HLB-related excessive fruit drop. This suggests that control of Diplodia fungal infection in the field may reduce HLB-associated pre-harvest fruit drop. [ABSTRACT FROM AUTHOR]

Peach-to-nectarine mutants showed broad pleiotropic effects on fruit size, taste, and aroma, in addition to hairlessness. In this study, we compared nine fruit attributes and 27 detected volatiles in the peach progenitor, 'Flameprince' (FPP), its two independently discovered peach-to-nectarine mutants (HFN and PFN), and a selected nectarine hybrid (SLN). HFN and PFN differed from FPP in fruit size and taste, but shared high similarities in fruit blush coverage and pattern, pit shape, and flesh and pit color. Compared to FPP, the two mutants were significantly lighter and smaller, but higher in soluble solids content (SSC), titratable acidity (TA), and the SSC/TA ratio. The 27 volatiles varied among the cultivars and harvest dates, in terms of total abundance and detection rate, and could be roughly clustered into six subgroups. Subgroup 1 included five volatiles and two fruit attributes that were low on Aug 6 but dramatically increased on Aug 13. Subgroup 2 had a similar tendency to subgroup 1 but one of the cultivars was an exception. Subgroup 3 included those that had the opposite tendency to subgroup 1 or 2. Volatiles in the three subgroups appeared closely associated with the ripening process. Fruit volatiles and attributes in the other three subgroups generally were inconsistent among the four cultivars on the two dates. Hexanol was the only volatile undetected in the peach, but detected in the three nectarines. Differences in broad pleiotropic effects among these mutants, potential utilization of volatiles, and genomic exploration are discussed. [ABSTRACT FROM AUTHOR]

BACKGROUND Mandarins and mandarin hybrids have excellent flavor and color attributes, making them good candidates for consumption as fresh fruit. When processed into juice, however, they are less palatable, as they develop delayed bitterness when stored for a period of time. In this study the kinetics of delayed bitterness in two citrus mandarin hybrid siblings, 'Ambersweet' and USDA 1-105-106, was explored by sensory and instrumental analyses. In addition to the bitter limonoids, other quality factors (i.e. sugars, acids, pH, soluble solids content ( SSC), titratable acidity ( TA) and the ratio SSC/ TA) were also measured. RESULTS The two citrus hybrid siblings had different chemical profiles, which were perceived by taste panels. USDA 1-105-106 developed delayed bitterness when the juice was stored for more than 4 h, similar to juice from 'Navel' oranges, but 'Ambersweet' did not. Bitterness in 'Ambersweet' was more affected by harvest maturity, as juice from earlier harvest had lower SSC but higher TA and bitter limonoids. CONCLUSION Since juice of USDA 1-105-106 shows delayed bitterness when stored for more than 4 h, this cultivar is not suitable for juice processing. Our finding that siblings can differ in chemical and sensory properties emphasize the importance of post-processing storage studies before releasing cultivars for juice. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Warm field temperatures can often result in poor peel color of some citrus varieties, especially early in the harvest season. Under these conditions, Florida oranges, temples, tangelos, and K-Early citrus fruit are allowed to be treated with Citrus Red No.2 dye (CR2) to help produce a more acceptable peel color. Unfortunately, CR2, the commercial colorant used in Florida, has been listed as a group 2B carcinogen by the European Union (EU) and the International Agency for Research on Cancer (IARC). Although not likely dangerous at levels used on citrus, and on a part of the fruit that is not ingested, there is a negative health perception, and thus, a need for natural or food grade alternative colorants to replace CR2 for use on citrus. This research demonstrated that three out of five oil-soluble natural red/orange colorants resulted in peel colors somewhat similar to the industry standard CR2. These three (annatto extract, paprika extract, and paprika oleoresin) were selected for further in vivo studies. The stability of the natural colorants along with CR2 was evaluated by applying them on test papers and then on fresh 'Hamlin' oranges. All natural colorants were found to be easily oxidized and faded when applied on test papers. However, coating the colored surfaces with carnauba wax apparently inhibited oxidation and the subsequent discoloration of the surface. When applying the natural colorants to 'Hamlin' oranges before waxing, the treatments retained the improved color after storage in the dark at 5 °C, simulating cold storage. However, only annatto extract maintained a stable color when subsequently stored in a simulated market condition, at 23 °C exposed to 300 lx of standard fluorescent white light. [ABSTRACT FROM AUTHOR]

The article offers information on the strawberry cultivar Sensation "Florida127" grown in Florida. Topics discussed include a description of the cultivar, the plant's origin and pedigree, and the advantage of its moderate plant size and long pedicels. Also mentioned are the marketable yield and average fruit weight of the variety.

Chilling exposure of tomato fruit to 5 °C for less than 5 days at mature green stage does not cause visual symptom of chilling injury (CI), however, it is unknown whether such conditions would impact flavour quality (internal CI) after ripening, and if a pre-chilling heat treatment could alleviate internal CI. In this experiment, mature green ‘FL 47’ tomatoes were gassed with ethylene to initiate ripening before heating and/or chilling treatment, and fruits were ripened at 20 °C after short exposure to the high or low temperature. Volatile analysis of the fruits were conducted after ripening. Chilling treatment generally suppressed production of aldehyde, alcohol, ketone, ester, acid and terpene volatile compounds, including the following abundant and/or important volatiles: hexanal, trans -2-hexenal, 6-methyl-5-hepten-2-one, β-ionone, 2-methylbutanal, 2-phenylethanol, guaiacol and 2-isobutylthiazole. Heat treatment alone did not affect most volatile levels after ripening. Heat treatment prior to chilling exposure alleviated the reduction of some key volatile compounds caused by chilling exposure, which agreed with sensory panel results in that panellists perceived more tomato flavour in “heating + chilling” treated fruit than fruit that were chilled only. [ABSTRACT FROM AUTHOR]