Using Chitosan Combined Treatment with Citric Acid as Edible Coatings to Delay Postharvest Ripening Process and Maintain Tomato ( Solanum lycopersicon Mill) Quality

Abstract

Physicochemical properties of citric acid and chitosan treated fresh tomato fruits were investigated in the present study. The experimental results showed that control fruits had higher weight loss, lower firmness and pH, but tomatoes-treated with chitosan and citric acid had no significant effect on pH, Vc, TSS and firmness, but significantly increased the SOD, POD, CAT and PAL activities of fresh tomatoes. All these treated tomato fruits maintained lighter color and higher contents of total phenolics and flavonoids, significantly decreased weight loss and MDA content of fresh tomato fruits compared to control. Of all these treated tomato fruits, citric acid + chitosan treatment maintained higher fruit quality, reduced the undesirable changes and protected the fruit tissues from injury. In short, the experiment datum indicated that citric acid + chitosan might be applied in a safe and effective preservative of fresh tomato fruits.