Postharvest Application of 1-Methylcyclopropene (1-MCP) Extends Shelf Life of Kiwifruit
The ethylene action inhibitor 1-MCP, which blocks the ethylene receptors, has been extensively studied to regulate fruit ripening in both climacteric and non-climacteric fruits.
Effect of 1-MCP on delaying softening of fruit has been reported to depend upon the fruit maturity stage at harvest, concentration applied, duration of fruit exposure to 1-MCP, method of application, storage conditions and fruit temperature at the time of 1-MCP application.
Treatment with 1-MCP extended the shelf life of kiwifruit by maintaining firmness both in fruit free of ethylene and in fruit contaminated with ethylene (1.0 µl /L) during the cold storage time up to 4 months. This means that treatment with 1-MCP induces an extension of shelf life of kiwifruit even if the fruit suffer from contamination of ethylene during the cold storage due to the ethylene production by other commodities.
1-MCP protocol to follow to extend the shelf life of kiwifruit depends on the length and type of storage that is going to be performed with the fruit.
For short periods of cold storage (up to 60 d), the lack of improvement of the 1-MCP treatment when applying higher concentrations, or for longer periods of time, points out that 0.5 µl/L of 1-MCP during 12 h applied just after harvest would be the recommended protocol to use. On the other hand, when the period of time to be stored is longer than 60 days, the protocol to follow it will depend on if the fruit is free of ethylene contamination during cold storage or not. If the fruit will be stored without any other commodity, and potential ethylene contamination in the storage atmosphere is going to be removed, an application of 0.5 µl/L of 1-MCP during 12 h will be the best protocol to follow on kiwifruit. However, if the fruit is suspected to be in contact to ethylene produced either by the kiwifruit or by other commodities in the same cold room, 1-MCP exposure time should be increased to 24h.