Effects of ethylene treatment on postharvest quality in kiwi fruit

Abstract

The kiwi fruit (Actinidia deliciosa cv. ‘Hayward’) should be ripened at any step during postharvest handling before consumer consumption. This is essential for freshly harvested kiwi fruit. But, this requires correct temperatures and ethylene concentrations. More testing of a newly developed ethylene generator using charcoal for commercial purposes is needed. This study was conducted to investigate the optimum storage temperatures and the effect of ethylene on the postharvest quality of kiwi fruit. Three different ethylene concentrations of 10, 50, and 100 μL·L -1 were used on fresh kiwi fruit stored at different temperatures of 10, 15, and 20℃. The quality changes of the fruits were assessed by sensory evaluation and by measuring firmness, soluble solids content, titratable acidity, and ethylene production. Higher storage temperatures and ethylene concentrations softened the kiwi fruit quickly and led to the rapid loss of acidity while soluble solid contents of fruit increased to a significant extent during the same storage period. Similarly, the firmness of ethylene-treated fruits stored at 20 and 15℃ dramatically decreased in the experiment while treated fruits stored at 10℃ decreased only slightly. Quality characteristics of kiwi fruits stored at 15 and 20℃ were better than those of fruits at 10℃. With regards to the effect of temperature, fruits stored at lower temperatures took a longer time to ripen and retained their quality longer. The newly developed ethylene generator maintained the ethylene concentration in the 5 kg box at 40 - 400 μL·L -1 . The ethylene generator could also be used to soften persimmons.