PHYSICO-CHEMICAL CHANGES IN PEAR FRUITS IN RESPONSE TO POST HARVEST APPLICATIONS OF OXALIC ACID

摘要

To study the effect of oxalic acid (OA) on storage behaviour of 'Nijisseiki' pear, fruits were dipped in aqueous solutions of oxalic acid @ 2, 4 and 6 m mol L"' for 4-5 mins. Treated as well as untreated (control) fruits were packed in corrugated fibre board (CFB) boxes and stored at low temperature conditions (0-1 °C and 90-95% RH) for 70 days. Fruits were analyzed for various physical and chemical changes after 30, 50 and 70 days of storage. Oxalic acid treatments were found effective in decreasing physiological loss in weight (PLW), spoilage and maintained the fruit firmness, sensory quality, total soluble solids (TSS), titratable acidity (TA), total sugars content and pectin methyl esterase (PME) activity as compared to control fruits under cold storage conditions. Postharvest application of oxalic acid delayed the ripening process of fruits. Among all the treatments, oxalic acid @ 6mmolL-l was most effective in retaining postharvest quality and reducing physio-chemical losses of pear fruits.From the present investigations, it can be inferred that oxalic acid treatment could be a promising way for extending the shelf life of pear under low temperature conditions.