Effects of 1-methylcyclopropene (1-MCP) and ethylene absorbent on softening and shelf life of dry ice-treated Japanese persimmon 'Saijo' harvested at various maturation stages

Abstract

Effects of 1-methylcyclopiopene (1-MCP) and an ethylene absorbent (active carbon containing palladium chloride) treatment on fruit softening and shelf life after removal of astringency by dry ice (CO2) in Japanese persimmon 'Saijo' (Diospyros kaki Thunb.) harvested at various stages, were investigated. At the end of the dry ice treatment, 78.1% of the control (non-treated) fruit harvested at the early stage (October 1) softened, whereas no control fruit harvested at the middle stage of the harvesting season (between October 22 and 29) softened, 50.0% of the control fruit harvested on November 11 softened. The ethylene concentration in the polyethylene bag 48 hours after start of dry ice treatment was highest in fruit harvested at the early stage. It decreased gradually in fruits harvested at a more mature stage. Both 1-MCP and ethylene absorbent treatments significantly decreased the fruit softening rate after the removal of astringency in fruit harvested at the early stage. However, there was little inhibitory effect of 1-MCP and ethylene absorbent on the softening of fruit harvested at the late stage. In fruit harvested at the middle stage, 1-MCP treatment prolonged the shelf life of fruit by about 6 days, compared to the non-treated control fruits, the ethylene absorbent treatment was ineffective in prolonging shelf life.