POSTHARVEST CHANGES IN TOTAL SOLUBLE SOLIDS AND TISSUE PH OF CHERIMOYA FRUIT STORED AT CHILLING AND NON-CHILLING TEMPERATURES

Total soluble solids (TSS) and pH were determined in cherimoya fruit ( Annona cherimola Mill.) stored at several temperatures. TSS increased from about 8.3-degrees Brix to 22-degrees Brix during 4 d of ripening at 22-degrees-C. At the same time fruit pulp pH declined from 6.2 to 4 .3. Similar values in TSS and pH, were not reached until the tenth day at 12-degrees-C. Fruit stored at 4-degrees-C underwent a slower incre ase in TSS and the decrease in pH was less than 1 unit. Storage at 1-d egrees-C for 27 d did not modify pH, and TSS increased by only 2-degre es Brix. Chilling injury was dependent on the length and temperature o f storage. Fruit rewarmed to 22-degrees-C after storage for 11 d at 4- degrees-C underwent changes in TSS and pH similar to those found in fr uit placed directly into 22-degrees-C air; on the contrary, pH was not modified when the chilling storage was for 15 d. However, rewarming o f fruit previously stored at 1-degrees-C resulted in a slight increase in TSS and little change in pH.