The role of endogenous antioxidants in scald development of 'Beurré D'Anjou' pears under different storage systems

Abstract

The role of endogenous antioxidants in scald development of 'Beurré D'Anjou' pears stored in regular air (control), low oxygen (LO) and treated with 1-methylcyclopropene (1-MCP) was studied. Superficial scald, ethylene production, α-farnesene (AF), conjugated trienols (CTols), total antioxidant capacity (DPPH), total polyphenols (TPF) and ascorbic acid content (AsA) were determined after 0, 15, 30, 60, 90, 120, 180, 210 and 240 days of cold storage. Control fruit produced ethylene prior to those stored in LO or treated with 1-MCP, which favoured AF accumulation and subsequent oxidation. After 60 days of storage, control fruit exhibited a maximum AF accumulation and low antioxidant potential associated with a decrease in TPF and AsA. Under these conditions, CTols increased rapidly, causing cell damage and severe scald symptoms after 180 days of storage. LO storage delayed the onset of ethylene production, AF accumulation and oxidation, and delayed the decrease in antioxidant potential leading to lower scald incidence. Similarly, 1-MCP treatment inhibited scald incidence through its action on ethylene production and AF synthesis but also maintaining the antioxidant potential and especially AsA levels during storage. Collectively, these results show that antioxidant potential and especially AsA may play an important role in the development of superficial scald in 'Beurré d'Anjou' pears.