EFFECT OF STORAGE TEMPERATURE AND TIME ON QUALITY IN MINIMALLY PROCESSED LITCHI FRUIT (LITCHI CHINENSIS SONN.)

Rind browning is the most serious marketing problem for litchi (Litchi chinensis Sonn.) fruit, although it has no effect on the quality of the edible aril portion. Physicochemical, biochemical and subjective quality evaluations were done in minimally processed (peeled and vacuum-packed) litchi cv. Racimo Rojo fruit stored 18 days at 2, 5 or 10C. Little change was observed in total soluble solids, titratable acidity and pH, independent of storage temperature. Polyphenol oxidase (PPO) activity decreased, total phenolic compound content remained unchanged and peroxidase (POD) activity increased during storage. Correlation was low (< 0.63) between color parameters (L*, a* and b*) and PPO and POD activities, and phenolic compounds. The minimally processed fruit stored at 2C exhibited characteristics similar to fresh fruit, whereas those stored at 5 and 10C emitted disagreeable odors that lowered their subjective quality. PRACTICAL APPLICATIONS The insignificant physicochemical changes observed here suggest that when stored at 2C, litchi fruit can be offered as a minimally processed product with characteristics similar to fresh fruit. Unlike most other minimally processed fruit products and other litchi varieties, pulp browning was not a significant problem in litchi cv. Racimo Rojo after peeling, providing it a potential commercial advantage.