Effect of Oxalic Acid on Control of Post-harvest Browning of Litchi (Litchi chinensis L.)

Abstract

Post-harvest browning of litchi is a common phenomenon that occurs due to enzymatic and non-enzymatic reactions. Enzymatic browning is primarily caused by polyphenol oxidase (PPO) activity, leading to the formation of brown pigments. Non-enzymatic browning is caused by the Maillard reaction between reducing sugars and amino acids. Factors such as temperature, humidity, and mechanical damage can accelerate browning. Proper handling, storage, and the use of antioxidants can help minimize post-harvest browning, extending the shelf life and maintaining the visual appeal of litchi fruits. The present investigation was laid out in the post-harvest laboratory of horticulture department, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj during the year 2022-2023. The experiment was laid out in the CRBD with 8 treatments and 3 replications. Litchi fruit, Cv. Purvi (about 80%- matured stage), were harvest from a Local market Prayagraj, fruit was selected for uniformity of size and colour, and blemished and diseased fruit were discarded. The selected fruit were dipped in different oxalic acid concentration solution (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 and 4.0mM) and Bavistin (0.05mg) as the control) for 10 mint 4 h of harvest, and then air dried. Each 10 fruit of the treated fruit was packed into a plastic punnet and wrapped with a 0.2-mm polyethylene bag, and then stored in an ambient condition. Post-harvest storage studies revealed that under ambient and refrigerated storage conditions T8 Oxalic acid (4.0mM) + Bavistin (0.05%) treatment showed slower rate of reduction on fruit length (cm) and fruit weight (g), browning (%) were significantly affected by treatments. There was significant effect of treatments on chemical parameters like pH, TSS (0Brix), acidity (%), ascorbic acid (mg100g), reducing sugar under ambient and refrigerated storage at different day’s intervals.