Submitted to: Meeting Abstract
Publication Type: Other
Publication Acceptance Date: 8/2/2004
Publication Date: 8/9/2004
Citation: Mattheis, J. 2004. Postharvest quality managment of apples: Current trends and practices. IN: C.L. Kreuz, A. Suzuki (eds). Proc. Enfrute 7, National Meeting on Temperate Tree Fruit Production. p. 227-230.
Technical Abstract: A primary objective of postharvest management of apples is to prolong storage life by reducing the rate of fruit ripening. The combination of optimum harvest timing, refrigeration, and storage in controlled atmospheres contribute to this goal, and the use of chemical treatments at harvest can reduce development of physiological disorders and decay. Collectively, these practices slow the rates of fruit respiration and quality loss in part through impacts on fruit ethylene production and action, processes that are required for ripening to occur. Controlled atmosphere (CA) storage reduces ethylene production as well as the capacity of fruit to respond to ethylene, responses that contribute to the residual effects of CA after fruit is removed from storage. Because of the importance of ethylene in regulating the processes of apple ripening, practices that interfere with its production and/or action are useful in the commercial storage of apples. Recognition by Drs. Sylvia Blankenship and Ed Sisler that 1-methylcyclopropene (1-MCP) is a powerful inhibitor of ethylene action has led to its development as a commercial tool for postharvest management of apple fruit. Apples exposed to 1-MCP treatment at harvest have a significantly delayed ripening, and development of a number of physiological disorders is also reduced or prevented. Fruit exposed to 1-MCP have delayed softening, acid loss, color change, aroma production, development of superficial scald, core flush, peel greasiness as well as other impacts on fruit quality. At the recommended dose and treatment duration, responses are governed by a number of factors including cultivar, fruit maturity at harvest and time of treatment, post-treatment storage conditions and duration of storage. The spectrum of physiological processes regulated by ethylene includes responses to stress. As such, the positive impacts of 1-MCP on maintenance of apple fruit quality must be balanced with the potential for enhanced susceptibility to environmental factors during storage. For some cultivars, treatment with 1-MCP can enhance susceptibility to low temperature and/or CA gas composition. Identification of situations where 1-MCP enhances the risk of injury continues to be an objective of apple research.