Effect of Postharvest Calcium Treatments on Internal Breakdown and Respiration of Apple Fruits1

Abstract

Abstract Dipping ‘Jonathan’ apples in CaCl2 solution prior to storage greatly reduced the development of internal breakdown (IB) and retarded flesh softening during 19 weeks at 2.2°C plus 1 week at 23°C. Infiltration of fruit with sorbitol produced IB symptoms, whereas glucose caused a dissimilar browning coloration and sucrose yielded no visible damage. Infused Ca inhibited IB symptoms and browning, retarded respiration, reduced the metabolism of endogenous substrates, and increased the oxidation of exogenous substrates. The results suggest Ca inhibits IB by enhancing the uptake and compartmentation of substrates, particularly sorbitol.