Induction of chill-induced ripening in Fuji apples is a function of both temperature and time

Ethylene production is stimulated by chilling in some cultivars of apples, citrus, cucumbers and pears. The apple varieties Granny Smith, Lady Williams and Fuji can be induced to ripen by a period of chilling at 0°C in air, which hastens the onset of the rise in ethylene production. Fuji apples were susceptible to rapid ripening if stored in air at low temperatures (<10°C). The induction of rapid ripening occurred in both early and late harvested fruit and was correlated with increased activity of 1-aminocyclopropane-1carboxylic acid oxidase during low temperature storage. The induction of rapid ripening caused the fruit to soften more quickly after cold storage than after continuous exposure to 20° C. Rapid ripening could be prevented by storing fruit in controlled atmosphere (CA) storage (2% O2 and <1% CO2). Fruit had lower internal ethylene levels following CA storage than following low temperature air storage. The practical solution for growers would therefore be to store Fuji apples in CA, even for short periods, to optimise fruit quality for the consumer.