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Muscadines (Muscadinia rotundifoliaMichx) have a thick peel that is often discarded by consumers. To better understand the potential nutritional loss due to this practice, total anthocyanin concentration (TAC), total phenolic content (TPC), total antioxidant activity (TAA), and chemical attributes in peel and flesh of eight purple muscadine genotypes were evaluated to determine the nutritional value of each part. Muscadine genotypes that were used in this study included two commercial cultivars (‘Supreme’ and ‘Paulk’) and six selections (‘Ga.10-1-222’, ‘Ga.10-1-294’, ‘Ga.10-1-329’, ‘Ga.12-5-46’, ‘Ga.12-3-22’, ‘Ga.13-4-79’). Bioactive compounds, antioxidant activity, and titratable acidity (TA) were higher in the peel of all muscadine genotypes, while the flesh had more sucrose, glucose, and fructose. In the peel, TAC (20.68–37.53 mg L− 1), TPC (382.84-577.31 mg GAE L− 1), ellagic acid (5.44–15.5 µg mL− 1), TAA (436.07-1258.26 µmoles TE L− 1), total soluble solids (TSS, 11.45–16.62%), TA (0.64–1.17%), TSS/TA ratio (10.92–24.46), pH (3.42–3.82), sucrose (13.73–69.49 mg mL− 1), glucose (58.42–77.69 mg mL− 1), and fructose (19.26–26.84 mg mL− 1) varied significantly among different cultivars. Similarly, in the flesh, the ranges of TAC (0.38–2.33 mg L− 1), TPC (11.48–26.52 mg GAE L− 1), ellagic acid (0.02–0.3 µg mL− 1), TAA (14.65–21.62 µmoles TE L− 1), TSS (12.25–17.3%), TA (0.43–0.73%), TSS/TA ratio (19.44–35.34), and pH (3.44–3.73), sucrose (39.33-124.02 mg mL− 1), glucose (71.75–92.86 mg mL− 1), and fructose (24.25–32.25 mg mL− 1) were significantly different among different cultivars. The ‘Supreme’ peel exhibited the highest TAC, TPC, and TAA, while the peel of ‘Ga.12-3-22’ had the lowest values. In ‘Supreme’ fruit, the TAC values ranged from 0.382 mg L− 1in the flesh to 37.53 mg L− 1in the peel. The TPC values showed variability between 17 and 577 mg GAE L− 1in both flesh and peel. Furthermore, TAA values ranged from 1258 to 16 µmoles TE L− 1in both peel and flesh. The peel contained over 90% of the ellagic acid in the fruit, with ‘Ga.12-5-46’ peel having the highest ellagic acid overall. The ellagic acid content in the peel of ‘Ga.12-5-46’ was 15.5 µg mL− 1, which was 144 times greater than that in its flesh. ‘Ga.13-4-79’ had the highest TA in both peel and flesh. The highest sucrose content in both peel and flesh occurred in ‘Ga.10-1-329’ and ‘Ga.12-3-22’, while ‘Ga.12-5-46’ and ‘Ga.13-4-79’ had comparatively lower sucrose in flesh. Given the substantial phytochemical content present in muscadine peel, discarding the peel constitutes a missed opportunity of considerable magnitude to obtain the full nutritional benefits of muscadines.

•Responses of ‘Budd Blood’ blood orange evaluated at 6, 8, 10, and 12 °C for 60 days.•Temperatures of 10–12 °C promoted the highest increases in TAC, TPC, and TAA.•Anthocyanin increased by 2950 % at 10 °C and 3000 % at 12 °C compared with harvest time.•Glucose and fructose levels increased, with the highest levels found at 12 °C.

The postharvest life of lettuce (Lactuca sativa) is variable and negatively affected by mechanical injury, incomplete cooling, and poor genetic quality. Lettuce breeders are developing cultivars with a longer shelf life and rely on subjective, destructive, and time-consuming methods for quality analysis. One method of accelerating quality evaluations is known as accelerated shelf-life testing (ASLT), which has the potential to assist breeders in assessing lettuce quality and shelf life. The objective of this research was to determine the quality traits that significantly affect shelf life to develop an ASLT procedure to rapidly assess the postharvest quality of lettuce accessions in breeding programs. In Test 1, Romaine lettuce quality was evaluated using one subjective and five objective parameters during storage at 5, 10, 15, or 20 °C. Results determined that weight loss, lightness*, and hue* angle were best correlated with the overall appearance rating, whereas storage at 10 or 15 °C differentiated the shelf-life potential quickly and without excessive deterioration. In Test 2, these objective characteristics and storage temperatures were used to study rates of quality deterioration of a commercial Romaine cultivar (Okeechobee) and a breeding line (60182), both with long shelf lives, and a Batavia lettuce cultivar (La Brillante) with a short shelf life. Lettuce was evaluated during storage at 10 °C (winter and spring seasons) or at 15 °C (winter season). Weight loss was the most appropriate quality index for lettuce at these storage temperatures for a single harvest, whereas lightness* and hue* angle were the most appropriate indices for comparing quality between harvests. To apply ASLT to postharvest assessments of lettuce, breeders and other researchers should include two controls with good and poor shelf life (similar to 'Okeechobee' and 'La Brillante', respectively) as standard baseline cultivars during storage at either 10 or 15 °C. [ABSTRACT FROM AUTHOR]

Interest is growing among small-scale growers in grafting tomato (Solanum lycopersicum) for improved crop productivity. Healing of newly grafted plants is often considered to be a critical process requiring a highly controlled environment. Setting up healing chambers and managing healing conditions can be major challenges for small-scale producers that limit graft survival and discourage further attempts at using grafting technology. Here, we demonstrate a simple "chamberless healing" strategy for grafted tomato plants using regular indoor conditions without the need to install and manage a sophisticated healing chamber. We hypothesize that tomato can form a high-quality graft in a healing environment with relative humidity below 70% and ambient temperatures between 22 and 25 °C. 'Tribute' beefsteak tomato as the scion was grafted onto 'Estamino' rootstock in the 2018 experiment, whereas 'Multifort' and 'Shield RZ F1 (61-802)' were used as the rootstocks in the 2019 experiment. After grafting, the seedlings for the chamberless healing treatment were kept in uncovered seedling trays and misted with water two or three times per day. Seedlings in other treatments were placed in a humidity dome or wrapped chamber to maintain high humidity during the first few days after grafting. In the 2018 experiment, chamberless healing was compared with covered treatments with different ventilation times during the first few days after grafting. In the 2019 experiment, chamberless healing was compared with a standard graft healing chamber treatment to further validate its feasibility. In both 2018 and 2019, all treatments showed high graft survival rates (>85%) at 21 days after grafting (DAG), and plants from the chamberless healing treatment had a lower incidence of adventitious root growth than plants from other healing treatments (0% to 7% vs. 33% to 78%). In the 2019 experiment, no differences in graft union strength, photosynthetic rate, biomass accumulation, or flowering time were observed between the chamberless and standard healing treatments. Plants with chamberless healing were slightly (8%) shorter than the standard treatment at 21 DAG, but no difference was observed at 27 DAG. Although some additional management is required during healing to prevent water loss, the alternative chamberless system assessed in this study exhibited great potential to facilitate small-scale graft healing for producing grafted tomato transplants under standard indoor conditions without any sophisticated healing environment and management. [ABSTRACT FROM AUTHOR]

Fresh-cut mango (Mangifera indica) slices and chunks garner an exotic image and are highly appreciated for their unique flavor and nutritional value. However, processors tend to use firm unripe mangoes to achieve shelf life of 10 to 14 days, which compromises eating quality. The post-processing life of ripe freshcut mangoes is limited by tissue softening, translucency, and browning. The current study was undertaken to investigate whether edible coatings can extend the shelf life of fresh-cut mangoes processed at an eating-ripe stage. Three edible coatings, carboxymethylcellulose (1% w/v), aloe (Aloe vera) powder (2% w/v), and whey protein isolate (2% w/v), supplemented with calcium ascorbate 2% w/v (firming agent) and the antioxidants citric acid (0.8% w/v) and acetyl-N-cysteine (0.4% w/v), were used. The mixture of antibrowning agents, whether applied alone or with the edible coatings, was the most effective at reducing slice browning up to 10 and 11 days at 5 °C for 'Tommy Atkins' and 'Kent', respectively. In general, there were no differences in firmness and flavor among the three edible coatings. Calcium ascorbate alone did not suppress browning consistently, whereas citric acid appeared to be the ingredient having the greatest antibrowning effect on slice quality. Citric acid can easily be used by processors of fresh-cut mangoes to prevent browning. [ABSTRACT FROM AUTHOR]

Fresh-cut mango (Mangifera indica) slices and chunks garner an exotic image and are highly appreciated for their unique flavor and nutritional value. However, processors tend to use firm unripe mangoes to achieve shelf life of 10 to 14 days, which compromises eating quality. The post-processing life of ripe freshcut mangoes is limited by tissue softening, translucency, and browning. The current study was undertaken to investigate whether edible coatings can extend the shelf life of fresh-cut mangoes processed at an eating-ripe stage. Three edible coatings, carboxymethylcellulose (1% w/v), aloe (Aloe vera) powder (2% w/v), and whey protein isolate (2% w/v), supplemented with calcium ascorbate 2% w/v (firming agent) and the antioxidants citric acid (0.8% w/v) and acetyl-N-cysteine (0.4% w/v), were used. The mixture of antibrowning agents, whether applied alone or with the edible coatings, was the most effective at reducing slice browning up to 10 and 11 days at 5 °C for 'Tommy Atkins' and 'Kent', respectively. In general, there were no differences in firmness and flavor among the three edible coatings. Calcium ascorbate alone did not suppress browning consistently, whereas citric acid appeared to be the ingredient having the greatest antibrowning effect on slice quality. Citric acid can easily be used by processors of fresh-cut mangoes to prevent browning. [ABSTRACT FROM AUTHOR]

Interest is growing among small-scale growers in grafting tomato (Solanum lycopersicum) for improved crop productivity. Healing of newly grafted plants is often considered to be a critical process requiring a highly controlled environment. Setting up healing chambers and managing healing conditions can be major challenges for small-scale producers that limit graft survival and discourage further attempts at using grafting technology. Here, we demonstrate a simple ''chamberless healing'' strategy for grafted tomato plants using regular indoor conditions without the need to install and manage a sophisticated healing chamber. We hypothesize that tomato can form a high-quality graft in a healing environment with relative humidity below 70% and ambient temperatures between 22 and 25°C. 'Tribute' beefsteak tomato as the scion was grafted onto 'Estamino' rootstock in the 2018 experiment, whereas 'Multifort' and 'Shield RZ F1 (61-802)' were used as the rootstocks in the 2019 experiment. After grafting, the seedlings for the chamberless healing treatment were kept in uncovered seedling trays and misted with water two or three times per day. Seedlings in other treatments were placed in a humidity dome or wrapped chamber to maintain high humidity during the first few days after grafting. In the 2018 experiment, chamberless healing was compared with covered treatments with different ventilation times during the first few days after grafting. In the 2019 experiment, chamberless healing was compared with a standard graft healing chamber treatment to further validate its feasibility. In both 2018 and 2019, all treatments showed high graft survival rates (>85%) at 21 days after grafting (DAG), and plants from the chamberless healing treatment had a lower incidence of adventitious root growth than plants from other healing treatments (0% to 7% vs. 33% to 78%). In the 2019 experiment, no differences in graft union strength, photosynthetic rate, biomass accumulation, or flowering time were observed between the chamberless and standard healing treatments. Plants with chamberless healing were slightly (8%) shorter than the standard treatment at 21 DAG, but no difference was observed at 27 DAG. Although some additional management is required during healing to prevent water loss, the alternative chamberless system assessed in this study exhibited great potential to facilitate small-scale graft healing for producing grafted tomato transplants under standard indoor conditions without any sophisticated healing environment and management. [ABSTRACT FROM AUTHOR]

Although grower interest in high tunnel tomato (Solanum lycopersicum) production has increased in recent years, systematic high tunnel research conducted in humid, subtropical regions has been limited. The potential of tomato grafting to mitigate biotic and abiotic stresses makes it complementary to high-value production systems in high tunnels. In this 2-year study, grafted vs. nongrafted organic tomato production in high tunnels and open fields was investigated to determine possible synergistic effects of these two technologies. In 2016, high tunnels resulted in a significant increase of total and marketable yields, by 43% and 87%, respectively, over open field production. Grafting also significantly increased total and marketable yields over nongrafted plants by 34% and 42%, respectively. Cultivar effects demonstrated greater benefits with the implementation of high tunnel and grafting technologies for 'Tribute' (a beefsteak-type tomato) than for 'Garden Gem' (a plum-type tomato), as the increase inmarketable yield was 33% greater for 'Tribute' in high tunnels and 45% greater for 'Tribute' with grafting. In 2017, a delayed effective transplanting date and the lack of high tunnel summer season extension produced results that were generally cultivar specific. While grafting increased the total yield of both cultivars (by 18%),marketable yield was increased by grafting only for 'Tribute' in high tunnels (by 42%). Additionally, high tunnels improved marketable yield of 'Tribute' by 129% but had no effect on 'Garden Gem'. This demonstrated the consistent trend of the beefsteak-type tomato benefiting more from the combination of high tunnel and grafting technologies than the plum-type tomato. High tunnels reduced fruit decay and cracking by up to 71% compared with open field production. Stink bug (Pentatomidae) damage had the greatest impact onmarketable yields each season, reaching 13% and 34% of total yields in 2016 and 2017, respectively, and was unaffected by high tunnel production or grafting. This study revealed the benefits of integrating high tunnel and grafting technologies for enhancing organic production of fresh-market tomato in the humid subtropics, and demonstrated more research is warranted to establish regional planting dates and further optimize this high-value cropping system. [ABSTRACT FROM AUTHOR]

Cooling procedures used by blueberry (Vaccinium sp.) growers often may include delays up to 24 hours that can damage the fruit through rough handling and adverse temperatures, thereby potentially compromising quality and, subsequently, safety. The objectives of this experiment were to compare forcedair cooling (FAC) compared to hydrocooling without sanitizer (HW) and hydrocooling with sanitizer (HS) regarding the quality and shelf life of southern highbush blueberry [SHB (Vaccinium corymbosum)] and to determine the efficacy of these treatments for reducing Salmonella in SHB. Freshly harvested SHB that were inoculated with a five-serovar cocktail of rifampin-resistant Salmonella were rapidly chilled by FAC or hydrocooling (HW and HS) using a laboratory model system. FAC did not show any significant reduction (P > 0.05) in Salmonella or in the effects on the microbiological quality of blueberries. HW and HS reduced Salmonella by °2 and >4 log cfu/g SHB, respectively, on day 0. These postharvest treatments were also evaluated for their ability to help maintain fruit quality throughout a storage period of 21 days at 1 °C. Hydrocooling (both HS and HW) provided more rapid cooling than FAC. Hydrocooled blueberries showed significant weight gain (P < 0.05), whereas FAC resulted in a slight, but insignificant (P > 0.05), reduction in final weight. The results of hydrocooling, both HS and HW, shown in this study could help to extend the shelf life while maintaining or increasing the microbiological quality of fresh market blueberries. Information obtained by this study can be used for developing the best temperature management practices to maintain the postharvest safety and quality of blueberries. [ABSTRACT FROM AUTHOR]

Grafting is considered to be a unique component in sustainable vegetable production. In addition to its usefulness for managing soil-borne diseases, it has been suggested that grafting with vigorous rootstocks can improve crop growth and yield. The objective of this greenhouse study was to assess the effects of different interspecific hybrid tomato rootstocks (Solatium lycopersicum × Solatium habrochaites) on yield, growth, nutrient accumulation, and fruit composition of tomato (S. lycopersicum). Using the determinate tomato cultivar Florida 47 as the scion, plants were grafted onto four interspecific rootstock cultivars including Beaufort, Maxifort, Multifort, and RST-04-105. Overall, the use of rootstocks resulted in total and marketable fruit increase 53% and 66% higher than non-grafted and selfgrafted scion plants, respectively. The increase in marketable yield by 'Beaufort', 'Maxifort', and 'Multifort' was largely attributed to an increased number of fruit per plant, whereas higher average fruit weight contributed to the yield increase in plants grafted onto 'RST-04-105'. Self-grafting of 'Florida 47' resulted in similar yield as the non-grafted scion control. Analyses of plant growth parameters demonstrated significant enhancement of total leaf area at first fruit harvest in plants grafted onto interspecific rootstocks as compared with the non-grafted and selfgrafted scion controls. In addition to plant growth and yield improvement, enhanced accumulation of nitrogen, potassium, and calcium was also observed in grafted plants. The enhancement in mineral nutrient accumulation was largely related to increased biomass accumulation rather than higher nutrient concentration (on a dry weight basis). The overall accumulation of phosphorus was not influenced markedly by the rootstocks used. In general, grafting with the interspecific rootstocks maintained fruit soluble solids content (SSC) and total titratable acidity' (TTA), concentrations of vitamin C, carotenoids, and total phenolics at levels comparable with non-grafted plants, whereas harvest date showed a more pronounced effect on fruit composition. [ABSTRACT FROM AUTHOR]

Gaseous 1-methylcyclopropene (1-MCP) delays mango (Mangifera indica) fruit ripening, but requires 12 hours of application in sealed containers. In some fruit species, aqueous formulation applied as a postharvest dip for only 1 to 5 minutes has shown the same effectiveness as gaseous 1-MCP. This research was conducted to determine the effectiveness of aqueous 1-MCP on delay of the ripening process, extension of shelf life, and maintenance of fruit quality of 'Kent' mango fruit with or without quarantine hot water treatment (QHWT). Three experiments were conducted during the 2013 season in Mexico and Florida and during the 2014 season in Mexico. Aqueous 1-MCP caused delay of fruit ripening as shown by maintenance of fruit firmness, attenuation of flesh color development, and delayed increase of total soluble solids (TSS). However, it had a negative interaction with QHWT, causing surface spots and lenticel blackening to develop during shipping simulation [3 weeks at 12 ± 1 °C, 90% ± 5% relative humidity (RH)] and market simulation (7 days at 22 ± 2 °C, 75% ± 10% RH). This negative interaction was less when 1-MCP was applied before QHWT, somewhat higher when 1-MCP was applied after QHWT, and most severe when 1-MCP was applied after QHWT + hydrocooling. By contrast, the ripening of fruit treated with 1-MCP without QHWT was delayed without affecting external appearance. Thus, 1-MCP may be more useful for mango markets that do not require mandatory QHWT. [ABSTRACT FROM AUTHOR]

As part of a larger project to show how fresh fruits and vegetables with enhanced flavor can he successfully handled to improve consumer satisfaction without compromising food safety, key informant interviews were conducted with fruit industry leaders dealing with melons (Cucumis melt and Citrullus lanatus), peaches and nectarines (Prunus persica), pears (Pyrus communis), tomatoes (Solanum lycopersicum), strawberries (Fragaria x ananassa), and blueberries (Vaccinium sp.). The interview was designed to collect information on industry attitudes and practices related to postharvest handling of more mature fruit, harvest timing, preconditioning, cold chain management, and shipping and handling procedures throughout the supply chain. The current analysis focuses on two key questions from the interviews: 1 ) To what extent do industry experts believe that better fruit handling and shipping procedures contribute to better taste quality in fruit? 2) To what extent do industry experts believe that better fruit quality will lead to more consumer purchasing? In response to the first question, the majority of respondents (70%) agreed that postharvest handling affects fruit flavor with the most cited themes related to agreement being gentle handling, cold chain management, and harvest tinting. Of the respondents who expressed disagreement most acknowledged the importance of postharvest handling, but felt other factors were also important, mainly the variety grown, the shelf life requirements, and the growing conditions. For the second question, 95% of respondents agreed that increased taste quality of fruit would mean increased purchasing and consumption. The primary theme related to agreement was that consumers would repeat purchase after positive eating experiences. Other important factors were the price point of fruit, retail display, product identity, and fruit appearance. With increasing consumer attention to fruit quality and a generally accepted belief among industry representatives that fruit flavor and quality drives consumer demand, there is an opportunity to shift industry practices toward postharvest handing that is conducive to consistently delivering better-tasting fruit to consumers. [ABSTRACT FROM AUTHOR]

The optimal ripeness stage for processing and marketing fresh-cut mangoes (Mangifera indica 'Kent') with best quality and maximum shelf life was determined. The initial ripeness stage selection was based on whole fruit firmness because this quality attribute was more reliable in predicting fresh-cut shelf life than flesh color or soluble solids content (SSC). Overall, the visual quality deteriorated differently and at different rates among ripeness stages. The shelf life, based on subjective visual evaluation, was 10, 7, and 5 days for ripeness stages corresponding to an average flesh firmness of 35, 30, and 25 N, respectively, and was mainly limited by desiccation and development of off-odor for the two firmer ripeness stages or symptoms of edge tissue damage and spoilage for the least firm stage. The slices from fruit with the highest initial firmness remained firmer during storage, had the lowest pH and SSC to titratable acidity (TA) ratio, and had the highest contents of volatile ketones and esters. The softest slices had the highest pH, SSC:TA ratio, and total ascorbic acid (TAA) content, as well as the lowest TA and highest volatile aldehyde and alcohol contents. Intermediate firmness slices had intermediate pH, SSC:TA ratio, color, and TAA content. Also, they had less volatile alcohols and aldehydes than slices from riper fruit but had similar content of esters as slices from the less ripe fruit. Therefore, based on the results from this study, an initial firmness of 30 N is recommended to process mangoes into fresh-cut slices because it assures the best quality and maximum shelf life based on textural, visual, and compositional attributes. [ABSTRACT FROM AUTHOR]

Grafting has many purposes in vegetable production. It is used for control of soilborne pathogens, season extension in protected culture, and improving productivity in cucurbitaceous and solanaceous crops. Consumers desire heirloom tomatoes (Solanum lycopersicum) for their perceived excellent flavor. Heirloom tomatoes are susceptible to many soilborne diseases and may benefit from grafting onto more robust, disease-resistant rootstocks especially under organic production. In this two-year study, heirloom tomato 'Brandywine' was grafted onto tomato hybrid 'Survivor' and interspecific tomato hybrid 'Multifort' rootstocks to determine the effects of grafting on fruit quality attributes such as soluble solids content (SSC), pH, total titratable acidity (TTA), and vitamin C. Nongrafted and self-grafted 'Brandywine' tomatoes were included as controls. Consumer sensory tests were also conducted to assess the effects of grafting on overall appearance and acceptability, firmness, tomato flavor, and sweetness. No significant differences in vitamin C, SSC, pH, or TTA were found in fruit from the nongrafted, self-grafted, and 'Brandywine' grafted with die two rootstocks either year. The SSC of all tomatoes in 2010 was lower than that of 2011. In 2010, fruit from 'Brandywine' grafted onto the rootstock 'Survivor' was scored significantly lower in appearance, acceptability, and flavor than the nongrafted 'Brandywine' treatment. All grafted treatments resulted in a significant decrease in acceptability ratings in die consumer sensory test. No significant differences were observed between nongrafted and grafted treatments in 2011. Consumers who reported more frequent consumption of fresh tomato tended to give lower ratings for most sensory attributes evaluated. Harvest time and fruit ripeness need to be considered in future research to better understand die influence of grafting with selected rootstocks on fruit composition and sensory attributes of heirloom tomatoes. [ABSTRACT FROM AUTHOR]

The efficacy of several proprietary plastic pallet cover systems to maintain strawberry (Fragaria xananassa) fruit quality during commercial shipment was determined. 'Albion' fruit were harvested from farms near Watsonville, CA. Fruit in vented plastic clamshells were palletized and forced-air cooled to 33-35 °F. Different cover systems (CO2 West, PEAKfresh, PrimePro, Tectrol) were placed over the pallets. Pads that released carbon dioxide (CO2) gas were placed inside the CO2 West cover. The Tectrol cover was sealed to the pallet base, a partial vacuum was applied, and pressurized CO2 gas was injected inside. The systems other than Tectrol remained open at the base. Six separate shipments of palletized fruit were transported in refrigerated (32-39 °F) truck trailers to distribution centers in either Florida or Georgia in 2.34.7 days. CO2 concentrations within pallets at the beginning and end of transport were highest (11% to 16%) in the sealed Tectrol system and relatively low (0.06% to 0.30%) in the open CO2 West, PEAK fresh, and PrimePro cover systems. Relative to noncovered control fruit, which lost 0.8% fresh weight during shipment, the pallet covers reduced the transport-related weight loss by 38% to 52%. The incidence of fruit decay was low (1.0% to 1.4%) after transport but increased substantially following a 2-day shelf life at 68 °F. However, fruit from the Tectrol pallets exhibited significantly less decay (36%) after shelf life than the CO2 West (39%), noncovered control (41%), PrimePro (42%), and PEAKfresh (43%) pallets. Fruit sensory quality was unaffected by the different pallet cover systems. Our findings show that transporting strawberries in the sealed Tectrol pallet cover system, in which CO2 concentrations were elevated to 11% to 16%, was most effective in complementing current low temperature management practices to maintain fruit quality. [ABSTRACT FROM AUTHOR]

Commercial shipments of strawberries (Fragaria xananassa) were evaluated from the harvest point to the distribution center (DC). Simulated retail conditions were afterward imposed on the fruit. Commercially harvested 'San Juan' strawberries in California were instrumented in the field for temperature and relative humidity (RH) monitoring during handling and distribution. At the cooling facility, five different treatments were imposed on five pallets of strawberries: prompt precooling to a final temperature of 1.7 or 10.0 °C, 4-hour delayed precooling to a final temperature of 1.7 or 10.0 °C, and no precooling. Immediately before being loaded into the trailer, all pallets were wrapped in a modified atmosphere (MA) pallet shrouds. Upon arrival at the DC in Florida, fruit from the same five pallets were exposed to three simulated retail temperatures (0, 6, and 21 °C) for 3 days. Results from this study showed that the refrigerated trailer was unable to maintain the temperature of any of the pallets during transport. In addition, upon arrival at the DC in Florida, strawberries from the partial precooling (cooled to 10.0 °C), 4-hour delayed precooling, and no precooling treatments had higher water loss and lower visual quality compared with fruit that were immediately precooled to a final temperature of 1.7 °C. On the basis of the quality control standards of the cooling facility in California, most of the fruit from the no precooling treatment were considered unacceptable for shipment 1 day after harvest. During simulated retail display, quality of the fruit held at 21 °C was inferior to that of fruit maintained at 0 or 6 °C, particularly that of fruit from the partial and delayed precooling treatments. Strawberries from the prompt precooling to a final temperature of 1.7 °C treatment had acceptable visual quality after simulated retail display for 3 days at 0 °C, whereas visual quality of the fruit from the delayed or partial precooling treatments ranged from slightly poor to poor after the same period of time. The presence of bruises due to mechanical damage shortened the shelf life of the fruit because of accelerated development of decay. Overall, results obtained from this study highlight the importance of prompt precooling and the use of optimum storage temperature (i.e., 0 °C) throughout the distribution chain and during retail display. [ABSTRACT FROM AUTHOR]

It has been reported that netted muskmelons (Cucumis melo var. cantalupensis) treated with moist heat (steam or hot-water immersion) have reduced populations of vegetative surface organisms that may be responsible for spoilage, or that may be pathogenic to consumers. It is unknown, however, what affect a similar heat treatment may have on infesting bacterial endospores (which are dormant, nonreproductive structures that are resistant to environmental stress). Also, any heat treatment used must be effective without exceeding the treated melon's thermal damage threshold. In this study, natural microflora on muskmelon rind pieces treated from 75 to 95 °C for 3 minutes and whole fruit rinds inoculated with Bacillus atrophaeus spores and treated at 85 °C for 3 minutes were observed as a model system to explore the efficacy of moist heat in reducing surface populations of bacterial spores. There were significant reductions in populations of aerobic, nonspore-forming microbes, although the treatments had little to no effect on either the recoverable populations of inoculated B. atrophaeus spores or indigenous spore-forming bacteria. Recovery studies suggested a less than 2 log10 unit reduction of inoculated B. atrophaeus spores after a 3-minute, 85 °C moist heat treatment, and no heat injury symptoms developed on melons during storage for 2 weeks at 5 °C. Increasing treatment temperature from 75 to 95 °C resulted in no increase in efficacy in terms of recovery of indigenous vegetative bacteria. The results of this study suggest that aqueous heat treatment is not a suitable method for reducing populations of the resting structures of spore-forming bacteria from the surface of netted muskmelons. [ABSTRACT FROM AUTHOR]

The effect of ethylene on the survival of Salmonella cells residing on unwounded surfaces of tomato (Solanum lycopersicum) fruit was investigated in this study. Inoculated fruit were stored in flow-through chambers that were adjusted to maintain an environment simulating a tomato ripening room. Fruit were held at 20 °C and ≥95% relative humidity after surface inoculation with the low virulence and rifamycin-resistant pathogen S. enterica ssp. enterica serovar Typhimurium strain LT2 (S. Typhimurium). Tomato fruit were treated either with a continuous flow (rate, ≈200 mL·min-1) of air or with ≥150 µL·L-1 ethylene in air. Bacterial recovery at 0, 24, 48, and 72 h after initiation of treatment showed that total populations of the S. Typhimurium cells declined in both the air and ethylene treatments during the first 24 to 48 h of storage, then increased to near initial levels by 72 h, similar to decline and recovery reported by other researchers in nonethylene treatment trials. These results suggest that although Salmonella can survive on the surfaces of tomato fruit in typical ripening rooms, proliferation of Salmonella is neither promoted nor inhibited by ethylene exposure. [ABSTRACT FROM AUTHOR]

Hydrocooling was evaluated as an alternative to forced-air cooling for strawberry (Fragaria x ananassa) fruit. 'Sweet Charlie' strawberries were cooled by forced-air and hydrocooling to 4 °C and held in different storage regimes in three different trials. Quality attributes, including surface color, firmness, weight loss, soluble solids, and ascorbic acid content, pH and total titratable acidity, were evaluated at the full ripe stage. Fruit hydrocooled to 4 °C and stored at different temperatures for 8 or 15 days showed overall better quality than forced-air cooled fruit, with significant differences in epidermal color, weight loss, and incidence and severity of decay. Fruit stored wrapped in polyvinylchloride (PVC) film after forced-air cooling or hydrocooling retained better color, lost less weight, and retained greater firmness than fruit stored uncovered, but usually had increased decay. There is potential for using hydrocooling as a cooling method for strawberries. [ABSTRACT FROM AUTHOR]

SUMMARY. Potassium (K) is required for successful carrot (Daucus carota) production on sandy soils of the southeastern United States, yet there is little published research documenting most current university Cooperative Extension Service recommendations. Soil test methods for K in carrot production have not been rigorously validated. Excessive fertilization sometimes is practiced by carrot growers to compensate for potential losses of K from leaching and because some growers believe that high rates of fertilization may improve vegetable quality. Carrots were grown in three plantings during the winter of 1994-95 in Gainesville, Fla., to test the effects of K fertilization on carrot yield and quality on a sandy soil testing medium (38 ppm) in Mehlich-1 soil-test K. Large-size carrot yield was increased linearly with K fertilization. Yields of U.S. No. 1 grade carrots and total marketable carrots were not affected by K fertilization. K fertilizer was not required on this soil even though the University of Florida Cooperative Extension Service recommendation was for 84 lb/acre K. Neither soluble sugar nor carotenoid concentrations in carrot roots were affected by K fertilization. The current K recommendation for carrots grown on sandy soils testing 38 ppm Mehlich-1 K could be reduced and still maintain maximum carrot yield and root quality. [ABSTRACT FROM AUTHOR]

A study was conducted to determine differences in sensory and compositional characteristics of melting-flesh (MF) and non-melting flesh (NMF) fresh market peach genotypes. Sensory results showed that the NMF fruit (‘Oro A’ and FL 86-28C) were ‘harder’, less ‘juicy’ and more ‘rubbery’ than their MF (FL 90-20 and ‘TropicBeauty’) counterparts. A principal component analysis of the sensory data showed a clear distinction between the textural aspects of MF and NMF fruit, but not between their flavour aspects. Likewise, chemical analysis showed that while differences in pH, titratable acidity, and soluble solids were detected among the four genotypes, no consistent grouping could be made based on the MF/NMF nature of the fruit. © 1999 Society of Chemical Industry