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Influence of preharvest sunlight exposure on superficial scald development in 'd'Anjou' pears during cold storage was investigated. The biochemical changes related to scald including α-farnesene, conjugated trienols (CTols), antioxidants, antioxidant enzyme activities were monitored among separated blushed and shaded peels of unbagged fruit as well as the whole peel of bagged fruit. In unbagged fruit, scald symptom was restricted to shaded peel; while there was no difference in α-farnesene between blushed and shaded peels, CTols increased significantly in shaded peel along with scald development after 3months storage. Bagging treatment increased both α-farnesene and CTols significantly and enhanced scald. Preharvest sunlight exposure significantly increased certain antioxidant contents and antioxidant enzyme activities in blushed peel at harvest and during storage. These results reveal a direct role of CTols during development of scald, however, antioxidant systems may play an important role in α-farnesene oxidation to CTols and scald susceptibility in 'd'Anjou pears.

To improve storage/shipping quality of sweet cherry (Prunus avium L.), the effect of calcium chloride (CaCl2) added to hydro-cooling water on physiological and biochemical processes related to fruit and pedicel quality was investigated on two major cultivars. The fruit tissue Ca content increased up to 29-85% logarithmically for 'Sweetheart' and 39-188% linearly for 'Lapins' as CaCl2 rate increased from 0.2% to 2.0% at 0 °C for 5 min. The increase of fruit tissue Ca content was accompanied by reductions in respiration rate, ascorbic acid degradation, and membrane lipid peroxidation, which enhanced total phenolics content and total antioxidant capacity, and resulted in increases in fruit firmness and pitting resistance and decreases in titratable acidity loss and decay of both cultivars. Pedicel browning was inhibited by CaCl2 at 0.2% and 0.5%, but increased by higher rates at 1.0% and 2.0%, possibly via modifying membrane lipid peroxidation.