Impact of Chitosan-Melatonin Composite Coating on Postharvest Quality of Sweet Cherry

The current research was conducted to test the effects of chitosan coatings enriched with melatonin on the storability of sweet cherry 'Sweetheart' fruit. Cherries were treated with water (control), 0.5% chitosan, 1000 mu mol l(-1) melatonin, and 1000 mu mol l(-1) melatonin + 0.5% chitosan for 5 min and stored at 0-1(degrees)C with 90-95% RH for 28 days. Weight loss, respiration rate, firmness, total soluble solids, titratable acidity, ascorbic acid, total anthocyanin, total phenolic, antioxidant content, decay incidence, and sensory quality were investigated weekly during storage. The results showed that the chitosan and melatonin + chitosan coatings could reduce both weight loss and respiration rate compared to uncoated fruits. Among treatments, chitosan coating enriched with melatonin significantly delayed the reduction of total soluble solids and firmness and kept higher biochemical content. Moreover, the addition of melatonin to the chitosan coating improved the antifungal effect of the formulation and improved sensory quality during storage. Consequently, the use of chitosan coating enriched with melatonin was an effective postharvest treatment to maintain the overall quality of sweet cherry fruits during storage.