Exogenous Application of Oxalic Acid Delays Pericarp Browning and Maintain Fruit Quality of Litchi cv. 'Gola'.

The present study was conducted to investigate the influence of oxalic acid on pericarp browning, biochemical quality, antioxidative and enzymatic changes in litchi cv. 'Gola' fruit under extended cold storage, which has not been studied extensively. Postharvest application of 2 mM oxalic acid reduced fruit weight loss and delayed pericarp browning by maintaining higher anthocyanin contents, as compared with control. Activities of polyphenol oxidase and peroxidase enzymes in litchi peel as well as pulp tissues were reduced in fruit treated with 2 mM oxalic acid during 28 days of cold storage. Activities of antioxidative enzymes (superoxide dismutase and catalase) and level of total phenolic contents and total antioxidants in litchi peel as well as pulp tissues were significantly higher in 2 mM oxalic acid-treated fruit. In conclusion, postharvest application of 2 mM oxalic acid significantly delayed pericarp browning and maintained better quality of litchi cv. 'Gola' fruit during cold storage. Practical Applications Pericarp browning of litchi fruit is associated with postharvest oxidative stress, which deteriorates its quality, long-term storability and commercial value. Postharvest application of oxalic acid has been found to be a useful strategy to overcome the issue of pericarp browning and enhance antioxidative potential of litchi under low temperature storage; thereby, applicable to commercial supply chains for domestic and export markets. Furthermore, this study may facilitate in understanding the changes in antioxidative potential and enzymatic activities during cold storage with gradual browning in pulp as well as peel tissues of litchi. [ABSTRACT FROM AUTHOR]