Study the apple fruit (Malus domestica cv. Fuji) browning factors, during storage

Enzymatic browning is one of the most important reactions that occur in fruits and vegetables, and usually resulting in negative effects on postharvest quality. In order to study the role of some important compounds on apple fruit browning and their changes during the storage, a completely randomized experimental design was conducted in Horticulture Research Center of Tehran University, on Fuji apple trees. In this study, changes of fruit browning, polyphenol oxidase activity, total antioxidant capacity, total phenolic content and the degree of membrane lipid peroxidation during 180 days of storage in 5 time intervals were analyzed. According to the results, total antioxidant capacityand polyphenol oxidase activity did not have significant changes during the first 90 days of storage, but both decreased significantly after 135 days. At the end of 180 days of storage, the lowest enzyme activity was recorded. Total phenolic contents in throughout the storage showed no significant changes. Lipids peroxidation after 90 days of storage increased significantly. Fruit tissue browning in the mid-storage decreased, but after 135 days increased significantly. It can be stated that possibly in the Fuji apple browning, total phenolic content as the enzyme activity is important and in addition to these two factors, lipid peroxidation index is very important in this process too.