Impact of postharvest hot salicylic acid treatment on aril browning and nutritional quality in fresh-cut pomegranate

In this study, we investigated the impact of hot salicylic acid treatment on the browning and nutritional quality of fresh-cut pomegranate arils during 12 days of storage at 4°C. Aril browning was concurrent with malondialdehyde (MDA) and H2O2 accumulation. Due to reduced polyphenol oxidase (PPO) activity in conjunction with higher phenylalanine ammonia-lyase (PAL) activity, pomegranate arils treated with hot salicylic acid exhibited higher total phenolic and anthocyanin contents during storage at 4°C for 12 days, leading to arils with higher DPPH radical scavenging capacity. Pomegranate arils treated with hot salicylic acid also exhibited lower H2O2 accumulation, which was caused by higher activity of the antioxidant enzymes catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD), and glutathione reductase (GR) during the storage period. The higher ascorbic acid content in pomegranate arils treated with hot salicylic acid can be attributed to higher APX/GR system activity. Thus, hot salicylic acid treatment not only enhances the health-promoting attributes of arils due to increased antioxidant molecule accumulation, but it also delays aril browning by increasing ROS scavenging enzyme activity, which helps maintain membrane integrity, as revealed by reduced MDA accumulation.