Effect of melatonin application on biochemical changes and maintaining the quality of persimmon

The purpose of this study is to determine the effects of melatonin dips on cold storage of the non-astringent 'Fuyu' persimmon cultivar. Persimmon fruits were subjected to different concentrations of melatonin (0 (control), 0.01, 0.1, and 1 mmol l−1 melatonin) and then stored at 0-1oC and 90-95 % relative humidity (RH) for 80 days. Weight loss, respiration rate, fruit firmness, total soluble solids (TSS), titratable acidity (TA), ascorbic acid, total phenolic, calyx appearance and chilling injury (CI) were examined at 20-day intervals. In the study, increasing doses of melatonin were found to be more effective in extending postharvest life. Among concentrations of melatonin application, 1 mmol l−1 melatonin-treated persimmon showed the preferable quality properties and lowest CI index. Moreover, this melatonin concentration caused a significant decrease in respiration rate and weight loss rate and maintained the fruit firmness, TSS and TA. While total phenolic content and ascorbic acid content were maintained by melatonin, it was determined that melatonin application had a non-significant effect on calyx appearance. Results obtained suggest that treating persimmon fruit with 1 mmol l−1 concentration of melatonin is effective in improving the postharvest quality and opens the possibility that higher concentrations of melatonin may be also effective.