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Three southern highbush blueberry cultivars (Vaccinium corymbosum hybrids) were mechanically harvested (MH) or hand-harvested (HH) and commercially packed before storage for 14 days at 1 °C in two successive years. MH fruit were softer, had lower ratings for overall appearance, and lost up to 20% more fresh weight than HH fruit after 14 days storage. MH ‘Meadowlark’ had fewer soft fruit (<35%) during storage than either ‘Sweetcrisp’ or ‘Farthing’; however, the latter two cultivars had lower incidences of shrivel and weight loss. Fruit in the 2010 season were more susceptible to bruising than those from the 2009 season; however, soluble solids content (SSC), total titratable acidity (TTA), and ascorbic acid concentration remained constant during storage and between seasons. ‘Meadowlark’ had the highest sugar to acid ratio (25.0). Successful implementation of MH of southern highbush blueberries for fresh market will only be commercially feasible if harvest impacts are further reduced.

Two Guatemalan-West Indian avocado (Persea americana) hybrids (‘Monroe’ and ‘Booth 8’) were treated with an aqueous formulation of 1-methylcyclopropene (1-MCP) to determine effects on ripening and quality during storage simulating commercial shipping temperatures. Fruit harvested at preclimacteric stage were immersed in aqueous 1-MCP at 75 μg·L⁻¹ (1.39 mmol·m⁻³) or in deionized water for 1 minute, stored at 10 °C for 14 days, and then transferred to 20 °C until ripe. Respiration rate, ethylene production, softening, and change in epidermal hue* angle were delayed and/or suppressed in both cultivars exposed to 1-MCP, although effects were less pronounced with Booth 8. Hue* angles for 1-MCP-treated ‘Monroe’ fruit had the highest values (darkest green peel color) of all treatments at full-ripe stage (hue* angle = 117). For control and treated ‘Monroe’ fruit respiration peaked on days 15 and 21, while ethylene production from both treatments peaked on day 16. Respiration and ethylene production peaked on day 16 for both control and 1-MCP–treated ‘Booth 8’ fruit. Fruit treated with 1-MCP consistently showed diminished respiration and ethylene peaks. Days to full-ripe stage were unaffected by treatment. ‘Booth 8’ fruit from both treatments were considered ripe (15 N whole fruit firmness) after 17 days; however, only 8% of control fruit were marketable, whereas 58% of 1-MCP-treated fruit were marketable, based on subjective appearance ratings using the Jenkins–Wehner score. The development of peel blemishes during storage was the primary cause of unmarketable fruit. ‘Monroe’ control and 1-MCP–treated fruit were soft after about 22 days and were significantly more marketable (control 70% and 1-MCP 85%). Avocados treated with 1-MCP ripened over a longer period than control fruit but maintained a higher percentage of marketable fruit.

`Solar Set' tomatoes (Lycopersicon esculentum Mill.) were harvested at the mature-green stage of development and treated with 50 μL·L^-1 ethylene at 20 °C. Breaker-stage fruit were dropped from 40 cm onto a solid surface to induce internal bruising and held along with undropped fruit at 20 °C. At the ripe stage, pericarp, locule, and placental tissues were analyzed for soluble sugars, vitamin C, pigments, titratable acidity, soluble solids content, pericarp electrolyte leakage, extractable polygalacturonase activity, and locule tissue consistency. Bruising significantly affected chemical composition and physical properties of pericarp and locule tissues, but not placental tissue. For bruised locule tissue, carotenoids, vitamin C, and titratable acidity were 37%, 15%, and 15%, lower, respectively, than unbruised fruit. For bruised pericarp tissue, vitamin C content was 16% lower than for unbruised tissue, whereas bruising increased electrolyte leakage and extractable polygalacturonase activity by 25% and 33%, respectively. Evidence of abnormal ripening following impact bruising was confined to locule and pericarp tissues and may be related to the disruption of cell structure and altered enzyme activity.

`Haden' and `Tommy Atkins' mangoes (Mangifera indica L.) were stored in air, 2, 3, 4 or 5 kPa O₂ plus N₂, or 25 kPa CO₂ plus air for 14 days at 15 °C or 21 days at 12 °C, respectively, then in air for 5 days at 20 °C to determine their tolerance to reduced O₂ levels for storage times encountered in typical marine shipments. All low O₂ treatments reduced mature green mango respiration (CO₂ production), however, elevated ethanol production occurred in 2 and 3 kPa O₂ storage, with the levels two to three times higher in `Tommy Atkins' than `Haden'. In contrast, `Haden' fruit at the onset of the climacteric also accumulated ethanol in 4 kPa O<sub>2</sub> and produced 10 to 20-fold more ethanol in 2 and 3 kPa O<sub>2</sub> than preclimacteric fruit. While there were no visible injury symptoms, off flavor developed in mature green fruit at 2 kPa O<sub>2</sub> and in ripening initiated fruit at 2 and 3 kPa O<sub>2</sub>. Ethanol production was not affected by storage in 25 kPa CO<sub>2</sub>. Ethylene production was reduced slightly by low O<sub>2</sub>, however, `Haden' fruit also showed a residual inhibitory effect on ethylene production after 2 or 3 kPa O₂ storage, while `Tommy Atkins' fruit stored in 2 kPa O<sub>2</sub> produced a burst of ethylene upon transfer to air at 20 °C. Fruit firmness, total sugars, and starch levels did not differ among the treatments, but 2, 3 or 4 kPa O<sub>2</sub> and 25 kPa CO<sub>2</sub> maintained significantly higher acidity than 5 kPa O<sub>2</sub> or air. The epidermal ground color responded differently to low O<sub>2</sub> and high CO<sub>2</sub> in the two mango cultivars. Only 2 kPa O<sub>2</sub> maintained `Haden' color better than air, while all low O₂ levels maintained `Tommy Atkins' color equally well and better than air. High CO<sub>2</sub> was more effective than low O<sub>2</sub> in maintaining `Haden' color, but had about the same effect as low O₂ on `Tommy Atkins'. Results indicate that preclimacteric `Haden' and `Tommy Atkins' mango fruit are able to tolerate 3 kPa O₂ for 2 or 3 weeks at 12 to 15 °C and that tolerance to low O₂ decreases as mangoes ripen. Results also show that low O₂ and high CO₂ affect mango ripening differentially.

Multi-state outbreaks of salmonellosis due to the consumption of contaminated fresh tomatoes (Lycopersicon esculentum) have recently occurred in the United States. This study investigated the survival of a five-serovar (serotype) Salmonella cocktail artificially inoculated onto tomato and packing line surfaces when held at various temperature and relative humidity (RH) combinations over 28 days. Packinghouse surfaces included stainless steel, polyvinyl chloride (PVC), sponge rollers, conveyor belts, and unfinished oak wood surfaces. Packinghouse climates were generated to simulate conditions in Florida during late spring (30 °C/80% RH) and fall/winter (20 °C/60% RH) months. Additionally, survival of Salmonella on tomatoes in standard ripening room conditions (20 °C/90% RH) was evaluated. Recovery of inocula was by a vigorous shake/hand rub method. After 28 days, Salmonella populations remained detectable on tomato surfaces regardless of environmental conditions. Inoculated Salmonella populations tested at spring conditions declined to undetectable levels on all packing line materials by day 11, with the exception of the unfinished oak, which reached undetectable levels by day 21. In contrast, inoculated Salmonella populations tested at fall/winter conditions declined to undetectable levels on sponge rollers and conveyor belts by day 7 and day 21, respectively. Stainless steel, PVC, and wood surfaces supported the survival of detectable populations of Salmonella over the 28-day sampling period. Results of this study demonstrate the potential for Salmonella to persist on tomato and packing line surfaces under common environmental conditions.

Hydrocooling was evaluated as an alternative to forced-air cooling for strawberry (Fragaria × 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.

Florida best management practices include the use of controlled-release fertilizers (CRFs), which are soluble nutrients coated with a resin, polymer, sulfur, or a polymer covering a sulfur-coated urea. The purpose of this study was to compare the effects of three CRFs (coated, homogenized NH₄NO₃ and urea, and coated KNO₃) rates in a hybrid CRF/soluble nitrogen fertilizer (SNF) system and two SNF rates [University of Florida/Institute of Food and Agricultural Science (UF/IFAS) and grower standard] on seepage-irrigated fall tomato (Solanum lycopersicum L.) yields, leaf-tissue nitrogen (LTN) concentration, postseason soil nitrogen (N) content, and postharvest fruit quality. Treatments of 112, 168, and 224 kg·ha⁻¹ CRF N plus 56 kg·ha⁻¹ SNF for total N of 168 (CRF112/SNF56), 224, and 280 kg·ha⁻¹ were compared with IFAS (224 kg·ha⁻¹) and grower standard (280 kg·ha⁻¹) of pre-plant SNF. Tomatoes were planted on 29 Aug. 2011 and 3 Sept. 2012 on polyethylene mulch. Air temperature averaged 23.0 and 22.6 °C for the 2011 and 2012 fall seasons with 33.4 and 37.4 cm of rainfall, respectively. Soil temperatures ranged from 15.2 to 40.1 °C in 2011 and 13.6 to 36.6 °C in 2012. Leaf tissue N concentration exceeded the UF/IFAS-recommended sufficiency range for all treatments and sample dates, except CRF112/SNF56 at the last sample date of 2012. There were no differences in extra-large and total marketable yield at first harvest nor in total extra-large yield (three harvests combined) among treatments in 2011; however, total marketable yield for UF/IFAS, CRF112/SNF56, 168/SNF56, and 224/SNF56 was greater than that of the grower standard. In 2012, CRF112/SNF56 and CRF168/SNF56 had the greatest first harvest extra-large and total yield, but there were no differences between season total marketable yields. No differences between treatments were found for total N remaining in the soil postseason in 2011 or 2012. The grower standard, UF/IFAS, and CRF112/SNF56 were firmer at red ripe (less fruit deformation) in 2011, but there were no differences in 2012. In 2011, CRF112/SNF56 and CRF224/SNF56 were rated highest in red color among the treatments, and in 2012 there were no differences. A hybrid system containing lower and equal N rates (112 to 168 kg·ha⁻¹ CRF N and 56 kg·ha⁻¹ SNF56) compared with UF/IFAS-recommended rates produced comparable marketable yield and fruit quality.

A study was conducted to determine the effect of 1-methylcyclopropene (1-MCP) on textural changes in fresh-cut tomato (Lycopersicon esculentum, Mill.) slices during storage at 5 °C. The relationship between fruit developmental stage and tissue watersoaking development was also determined. Fresh-cut tomato slices prepared from light-red fruit that had been exposed to 1-MCP (1 μL·L^-1 for 24 h at 5 °C) retained significantly higher pericarp firmness during storage at 5 °C for 10 d than slices from nontreated fruit or slices stored at 10 or 15 °C and they also had a significantly higher ethylene production maximum. 1-MCP (1 or 10 μL·L^-1 for 24 h at 5 °C) had no affect on the firmness of fresh-cut, red tomato slices at 5 °C or on slices prepared from 5 °C-stored, intact red tomatoes. Nor did 1-MCP treatment have a significant effect on electrolyte leakage of tomato slices or intact fruit stored at 5 °C. Slices from fruit of the same developmental stage but with higher initial firmness values had less watersoaking development and responded better to 1-MCP treatment during 8 d storage at 5 °C. 1-MCP (1 μL·L^-1) was more effective in reducing watersoaking in light red stage tomato slices when applied at 5 °C for 24 h compared with 1-MCP applied at 10 or 15 °C. Watersoaking development was also more rapid in fresh-cut tomato slices as initial fruit ripeness advanced from breaker to red stage. Our results suggest that watersoaking development in fresh-cut tomato slices is an ethylene-mediated symptom of senescence and not a symptom of chilling injury as had previously been proposed.

Tomato (Lycopersicon esculentum L.) fruits, cv. Solarset, were harvested at the mature-green stage and treated with 50 μL/L ethylene at 20C. Breaker fruits (<10% red coloration) were dropped from 40 cm onto a smooth, solid surface and held along with undropped fruits at 20°C and 85% relative humidity. At table-ripe stage, pericarp, placental, and locular tissue were individually excised and analyzed for total carotenoids, total soluble sugars, soluble solids content, titratable acidity, density (locule tissue), polygalacturonase activity, and electrolyte efflux (pericarp tissue). Internal bruising caused by impact forces significantly affected pericarp and locule tissues, but not placental tissue. For bruised locule tissue, total carotenoids content decreased by 37.1%, vitamin C content by 15.6%, and titratable acidity by 15.3% as compared to control. However, density was increased by 3.0%. For bruised pericarp tissue, vitamin C content decreased by 16.5%, while polygalacturonase activity and electrolyte efflux increased by 33.3% and 24.8%, respectively. The development of abnormal ripening following an impact was confined to locule and pericarp tissues and appears to be related to the disruption of cellular structure and stimulation of enzymic activity.

Strawberry (Fragaria ×ananassa Duch.) fruit are very susceptible to mechanical injury and for this reason are normally field-packed. Fruit of three cultivars (Chandler, Oso Grande, Sweet Charlie) were subjected to forced-air or hydrocooling to reach pulp temperatures between 1 and 30 °C and then individually subjected to compression and impact forces representative of commercial handling operations. Strawberries with a pulp temperature of 24 °C exhibited sensitivity to compression but greater resistance to impacts. As pulp temperature decreased, fruit were less susceptible to compression as shown by up to 60% reduction in bruise volume. In contrast, strawberries at 1 °C pulp temperature had more severe impact bruising with up to 93% larger bruise volume than at 24 °C depending on the cultivar. Strawberries also showed different impact bruise susceptibility depending on the cooling method. Impacted fruit that were forced-air cooled had larger bruise volumes than those that were hydrocooled. The impact bruise volume for strawberries forced-air cooled to 1 °C was 29% larger than for fruit hydrocooled to 20 °C, 84% higher than those forced-air cooled to 20 °C, and 164% higher than those hydrocooled to 1 °C. Because incidence and severity of impact and compression bruises are temperature-dependent, strawberry growers should consider pulp temperature for harvest scheduling and for potential grading on a packing line. Hydrocooling shows promise to rapidly cool strawberry fruit while reducing weight loss and bruising sensitivity.