Application of chitosan-based edible coating enriched with 24-epibrassinolide to maintain quality of late-harvested pomegranate fruit (‘Wonderful’)

This study evaluated the efficacy of 24-epibrassinolide (EBR) infused onto chitosan in preserving the postharvest quality of late-harvest pomegranate (‘Wonderful’) fruit. Late-harvest pomegranate fruit were immersed in different surface treatment solutions of CH; 1.5% (w/v), CH + 2 µM EBR, CH + 5 µM EBR, CH + 10 µM EBR, CH + 15 µM EBR, and distilled water was used as a control treatment. The fruit were stored at 5°C with 85±5 RH for 3 months, and measurements were taken at 4-week intervals. At each sampling point, a batch of fruit was placed at 21±2°C and 65-70% RH for a further 4 d period to simulate retail conditions. Fruit weight loss, texture, respiration electrolyte leakage, antioxidant capacity and decay were investigated. The results showed that the CH-based EBR composite edible coating significantly (p<0.05) delayed the changes in weight loss, texture, respiration, electrolyte leakage and reduced spoilage compared to the control fruit. The treatment effect was more noticeable on fruit treated with CH + 10 µM EBR, which exhibited lower weight loss (18.19%), electrolyte leakage (27.54%), decay (12.5%), respiration rate (7.72 mL CO2 kg^-1 h^-1) and maintained higher texture (10.8 N) and DPPH (1.99 mM AAE mL^-1) compared to the untreated fruit with respective values of 24.32, 43.15, 37.5%, 18.06 mL CO2 kg^-1 h^-1, 17.03 °Brix, 0.81%, 8.32 N and 1.79 mM AAE mL^-1. Overall, the results of this study show that CH + 10 µM EBR treatment could be recommended to preserve the quality of late-harvested pomegranate fruit during storage.