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Quality changes of bunched and topped radishes (Raphanus sativus L.) during postharvest storage were investigated. Bunched radish plants, topped roots and detached leaves were stored at 5 or 10C for 9 days. Yellowing and wilting of leaves during storage at 10C were the main visual quality deteriorations in bunched radishes. Leaf detachment reduced respiration and ethylene production rates and weight loss of roots, and resulted in lower ascorbic acid, antioxidant capacity and phenolic content especially during storage at 10C. Root color did not change during storage, with or without leaf detachment. Leaf color did not change at 5C, whereas lightness and chroma increased and hue angle decreased at 10C, with larger changes observed in detached leaves. H2O2 content as well as peroxidase, ascorbate peroxidase and catalase activities in the root tissue were unaffected by leaf detachment, but increased during storage especially at 10C after 9 days of storage. Practical Applications Radishes are marketed with the leaves attached on the enlarged root, which is the edible part of the plant, or are topped so that leaves are removed from the root. Consumers prefer to purchase radishes with the leaves attached because their green color is an indication of freshness. In retail market, higher than recommended temperatures are often encountered, resulting in yellowing of leaves; therefore, plants are topped and only the root is distributed. However, the effects of storage temperature as well as the removal of leaves on nutritional compounds of the edible roots have not been investigated and need to be determined, because nutritional quality is of increasing interest to the consumers. This study provides information on the effect of temperature and leaves removal on metabolism and quality of radish plants during storage, which can be applicable to sustain the quality and increase commercial marketing of radishes.

"Tommy Atkins" and "Palmer" mangoes were harvested medium-ripe held for 7-20 days at five different temperatures and evaluated for quality attributes. The objective of this work was to obtain quality curves at chilling and nonchilling temperatures and to identify, for each temperature, which quality factors limit mango marketability. Chilling injury and increased fruit softness were the limiting quality factors for mango stored at 2 and 5C. Softening of the fruit, changes in color and development of decay were the limiting quality factors for mango stored at 12, 15 and 20C. Prediction of mango shelf life calculated from the data reported in the literature is not precise unless the characteristics of the fruit and environmental factors involved are well known. The curves obtained from quality evaluations for each temperature showed that a single quality attribute cannot be used to express loss of quality of mango over the normal physiological range of temperatures.

“Rhapsody” tomatoes were not heated or heated in air at 34 or 38C and 95% relative humidity (RH) for 24 h then stored at 4 or 20C for up to 4 weeks. The fruits were severely injured by 38C exposure, while those heated at 34C were only slightly injured. Heated fruit had more weight loss than control fruit. Nonheated fruit and those heated at 34C developed the best color compared with fruit heated at 38C. There were no differences in chlorophyll degradation between heated and nonheated fruit stored at 4C; however, fruits that were not heated and stored at 20C were the only ones with chlorophyll that degraded completely. Fruit stored at 20C developed a high quantity of lycopene andβ-carotene, with the highest level obtained in fruit heated at 34C and stored at 20C. Fruit stored at 4C almost did not develop any carotenoids.

Greenhouse-grown pink tomatoes (cv. Buffalo) were stored in air or in a controlled atmosphere (CA) of 4% O2 plus 2% CO2, to study the effect of CA at chilling and nonchilling temperatures on fruit quality characteristics. Tomatoes could be stored in CA at 12C for three weeks with no major changes in fruit appearance. CA was effective in delaying color development and ripening at this temperature. The soluble solids content was lower after CA storage, but no significant differences in firmness, pH or titratable acidity were observed between storage in air or CA. Storage in CA at 12C was also effective in reducing decay. However, at 6C, fruit showed high incidence of decay after both air and CA storage. CA did not alleviate chilling injury symptoms relative to air-stored samples and may have caused CO2 injury. Water loss was greater under CA at both temperatures.

Previous studies suggested that modification of storage temperatures at the wholesale warehouse could sufficiently retard ripening to permit harvest of fresh-market tomatoes at a later maturity, thus allowing for greater flavor development on the vine. Tomatoes (cvs ‘Celebrity’ and ‘Sunny’) were harvested either at the breaker or pink stages of maturity. Simulated wholesale storage was conducted by holding breaker fruit for 3 days at 12°C or 21°C and pink fruit for 3 days at 5°C or 37°C. Short-term low- and high-temperature storage of pink tomatoes delayed ripening sufficiently to maintain acceptable color and firmness during retail and consumer storage at 21°C for 7 days. Flavor characteristics of tomatoes harvested at the pink stage of maturity were not significantly superior to those of fruit harvested at the breaker stage. Thus, although ripening can be delayed in pink tomatoes during postharvest handling, delaying harvest from the breaker to the pink stage does not offer the flavor advantage to warrant a change in the handling system.