Shelf life extension and antioxidant activity of 'Hayward' kiwi fruit as a result of prestorage conditioning and 1-methylcyclopropene treatment

Kiwi fruits (Actinidia deliciosa C.F. Liang et A.R. Ferguson) were treated by prestorage conditioning (20 A degrees C for 2 days), 1-methylcyclopropene (1-MCP, 1 ppm for 16 h) and conditioning plus 1-MCP. After the treatment the fruits were immediately stored at 0 A degrees C during 24 weeks. Flesh firmness gradually decreased with storage time and the rate of its loss was lower in 1-MCP and conditioning plus 1-MCP treatments than those of control or conditioning. However, SSC, acidity and pH did not change among treatments. Starch content decreased during the storage time regardless of treatments. Oppositely the amount of reducing sugars increased at the same duration of the treatments. Rate and incidence of fruit decay was the lowest in fruit treated with conditioning plus 1-MCP treatment. Fruit decay mainly caused pathogen Botrytis cinerea and its rate significantly decreased with conditioning plus 1-MCP treatment. Ethylene and respiration abruptly increased after 8 weeks of storage, but their contents were lower in 1-MCP and conditioning plus 1-MCP. Total soluble phenolics, flavonoids, and total antioxidant capacities were much higher than in other treatments. Kiwi fruits treated with conditioning plus 1-MCP extended the shelf life by reducing the rate of fruit decay and softening during the storage. The bioactive compounds and total antioxidant status of fruits increased during the treatment.