Salicyloyl chitosan alleviates chilling injury and maintains antioxidant capacity of pomegranate fruits during cold storage

•Salicyloyl chitosan alleviated chilling injury of pomegranate fruits during cold storage.•Salicyloyl chitosan enhanced membrane unsaturated/saturated fatty acids (unSFA/SFA) ratio.•Salicyloyl chitosan promoted total phenols, anthocyanins and ascorbic acid accumulation.•Salicyloyl chitosan enhanced hydrophilic (H-TAA) and lipophilic (L-TAA) antioxidant capacity.•Salicyloyl chitosan can be used as promising procedure for extending postharvest life of pomegranate fruits.

In this study, the effects of postharvest salicylic acid, chitosan and salicyloyl chitosan treatments on chilling injury and nutritional quality of pomegranate fruits during storage at 2 °C for 5 months was investigated. Chilling injury symptoms in pomegranate fruits were manifested by external husk browning and internal segment browning. Alleviation impacts of salicyloyl chitosan treatment on pomegranate fruits chilling injury was higher than salicylic acid and chitosan treatments along, which results to delay external and internal browning and increases in electrolyte leakage. Also, pomegranate fruits treated with salicyloyl chitosan exhibited higher membrane unsaturated/saturated fatty acids (unSFA/SFA) ratio. Higher hydrophilic (H-TAA) and lipophilic (L-TAA) antioxidant capacity in pomegranate fruits treated with salicyloyl chitosan results from higher total phenols, anthocyanins and ascorbic acid accumulation. In addition to nutritional quality, pomegranate fruits treated with salicyloyl chitosan exhibited lower weight loss, respiration rate and ethylene production associated with higher firmness, total soluble solids, and titrable acidity as sensory quality. These results suggest that salicyloyl chitosan treatment can be used as promising strategy not only for alleviating chilling injury by maintaining membrane integrity results from higher unSFA/SFA ratio but also for enhancing antioxidant capacity by total phenols, anthocyanins and ascorbic acid accumulation.

Graphical abstractDownload high-res image (113KB)Download full-size image