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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]

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]

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]

With 4 figures and 3 tables Abstract Many volatile compounds have been shown to influence the flavour of strawberry ( Fragaria spp.) fruit. A published study demonstrated that linalool, a critical flavour compound, is produced in cultivated F. × ananassa varieties owing to a truncated form of the NEROLIDOL SYNTHASE (NES) enzyme. The corresponding allele ( FaNES1) features a 5′-deletion that is detectable by PCR. Herein, we tested a broad set of strawberry genotypes to understand the origin of the allele and to identify materials that may be preferred candidates for molecular breeding. The results indicate that the FaNES1 allele (linalool+) is not present in any diploid, tetraploid or hexaploid accession tested. It is present in 112 F. × ananassa cultivars examined. The FaNES1 allele is present in all but three of 46 wild F. virginiana and F. chiloensis genotypes. Two of these three lines continue to produce linalool despite the absence of the allele. This survey suggests that the FaNES1 allele possibly arose following octoploidization and that linalool possibly is an important factor in strawberry biology, aside from its role in anthrocentric fruit quality attributes. [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]

• 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]

The objective of this research was to evaluate the use of a controlled-release carvacrol powder to delay storage decay and maintain the safety of blueberries. The controlled-release carvacrol powder was a microcapsule of carvacrol (11% (w/w) active carvacrol) surrounded by a pectin/sodium alginate matrix. The microcapsules were packed in an air-permeable pouch, and then attached to the top of a clamshell filled with blueberries. The blueberries, inoculated with Escherichia coli or Colletotrichum acutatum, or non-inoculated control, were monitored for microbial growth and quality for 10 days at 10 °C and 5 days at 20 °C. Three treatments were compared: controlled-release microencapsulated carvacrol, non-encapsulated carvacrol, and control. The results showed that both the microencapsulated carvacrol and the non-encapsulated carvacrol treatments significantly reduced the populations of yeast and mold, and of E. coli and mesophilic aerobic bacteria. The microencapsulated carvacrol treated berries retained better quality due to significantly lower weight loss than control after 10 days at 10 °C. Sensory panelists found that the microencapsulated carvacrol berries had significantly higher overall blueberry flavor and lower discernible off-flavor in comparison with the non-encapsulated treatment after 3 days at 20 °C. The fruit internal quality, including total soluble solids content (SSC), and titratable acidity (TA), was not significantly affected by any treatment. These results indicate that pectin/sodium alginate controlled-release microencapsulated carvacrol can be used for the preservation of blueberries or other small fruit. [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]

'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]

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]

The University of Florida strawberry (Fragaria xananassa Duch. ex Rosier) breeding program has maintained a continuous breeding effort since 1968 to develop cultivars that are highly adapted to winter production in west-central Florida. To gain insight into breeding progress over time, two advanced selections (UF1 and UF2) and 10 released cultivars, from Florida Belle (1975) to Florida Radiance (2008), were compared for various fruit quality traits in a two-location field study during the 2009-2010 season. Fruit size varied dramatically from 30.8 g for 'Elyana' to 16.2 g for 'Dover' at Balm, FL, and from 28.3 g for UF2 to 16.6 g for 'Dover' at Dover, FL. A linear regression of fruit size on year of release revealed an average gain of 2.6 g per year since 1975 for the cultivars and selections tested (R² = 0.44). A similar analysis revealed a reduction over time in the proportion of cull fruit (R² = 0.30). Gains were apparent for the redness of the internal flesh, from a colorimeter a* value of 16.1 for 'Florida Belle' (1975) to 34.7 for 'Carmine' (2002) but were not sustained for later releases and selections. Although there were significant differences among genotypes for all chemical traits affecting flavor, there were no discernable patterns over time. There were wide month-to-month variations in individual sugars and organic acids, except for citric acid, which was stable across months and locations. The ratio of soluble solids content to titratable acidity ranged widely among genotypes, from a high of 15.7 for 'Florida Belle' in February at Dover, FL, to a low of 6.4 for 'Winter Dawn' in January at Balm, FL. The observed variability and trends in fruit quality traits will help guide future genetic studies and inform decisions about future breeding priorities and selection procedures. [ABSTRACT FROM AUTHOR]

• Six SHB blueberry cultivars were observed for 2 years, 2 harvests, 2 storage weeks. • Indigocrisp and Keecrisp were the firmest and maintained firmness in storage. • Indigocrisp was the sweetest with highest blueberry flavor among cultivars. • Sensory firmness and sourness were highly correlated with instrumental measures. • Indigocrisp maintained its quality independent of environmental variables. Blueberry (Vaccinium spp.) is a specialty crop with expanding production and consumption worldwide. Southern Highbush Blueberries (SHB) require few chilling hours and include early-ripening cultivars which can be harvested in an early market window making the crop more profitable for growers in sub-tropical regions. To expand the marketability of the crop, fruit breeders are seeking to meet the current demand for fruit quality. To this end, this study gathered sensory measurements (firmness, sweetness, sourness, blueberry flavor, green flavor and off-flavors), chemical (pH, titratable acidity and soluble solids concentration), and physical attributes (compression force) on six SHB cultivars, in order to understand how fruit quality traits are affected by environmental conditions such as storage duration, year and harvest date. Differences across environmental conditions for all attributes were observed. Indigocrisp and Keecrisp were the firmest cultivars and maintained firmness over time in storage. Additionally, Indigocrisp was the sweetest and had the most blueberry and green flavors among the cultivars. On the other hand, Arcadia was the softest, as measured by sensory and compression force, but varied with year and harvest. Arcadia and Emerald were the least sweet and most sour of the cultivars, and Endura and Patrecia were intermediate for all sensory attributes. In general, sensory descriptors were well explained by instrumental measurements. Variations across seasons and storage were inconsistent among cultivars, but Indigocrisp was the most stable cultivar for the quality traits evaluated. In the end, all fruit quality traits assayed in this study were influenced by environmental conditions throughout the season. [ABSTRACT FROM AUTHOR]