Ripening of apples during storage: III.—Changes in chemical composition of Golden Delicious apples during the climacteric and under conditions simulating commercial storage practice

Golden Delicious apples were harvested pre‐climacteric and samples of fruit were stored in air at 12°C, air at 3°5°C,5% CO 2 /3 % O 2 at 3·5°C and 2%O 2 at 3°5°C. Chlorophyll and carotenoid in the fruit peel, alcohol‐soluble carbohydrate, titratable acidity and polysaccharide components of the alcohol‐insoluble residue of the fruit cortex were estimated after periods of storage. In fruit stored in air at 12°Cchlorophyll decreased and carotenoid increased rapidly, neutral pectic polysaccharides decreased and soluble polyuronide increased in the early stages of storage. At 3°5°C the pigment changes were retarded and further so in the modified atmosphere; loss of neutral polysaccharides occurred rapidly at first under all conditions but was arrested in 5 % CO 2 /3 %O 2 ; increase of soluble polyuronide occurred with little delay at 3°5°Cin air, after 113 days in 2%O 2 and was not observed in 5 % CO 2 /3% O 2 . Loss of sugar and acid were retarded at the lower temperature and further retarded by modified atmospheres. The implications of these results for commercial storage are discussed and an attempt is made to relate them in the developmental physiology of apple fruits.