Effect of irradiated chitosan on minimally processed 'wonderful' pomegranate arils during cold storage

Abstract

Developing postharvest protocols incorporating nonchemical compounds with the aim of extending shelf life and maintaining quality of fresh produce is of great importance. The potential of chitosan (irradiated and unirradiated) in preserving pomegranate arils (cv. Wonderful) during cold storage was investigated in this trial. Solid chitosan powder was gamma irradiated with 25 and 50 kGy doses, chitosan solutions were prepared and arils were treated prior to cold storage. Initial arils quality characteristics were assessed before refrigeration at 5 ^oC and RH 75 % for up to 15 day, during which studied characteristics were determined trice, with a 5 day interval. Different treatments were applied by immersion in one of the following for 2 min with: Control (distilled water); 0.5%, unirradiated chitosan; 0.5%, 25 kGy irradiated chitosan; 0.5%, 50 kGy irradiated chitosan; 1.0 %, unirradiated chitosan; 1.0 %, 25 kGy irradiated chitosan; 1.0 %, 50 kGy irradiated chitosan solutions). Results revealed that chitosan treatments reduced weight loss and controlled reductions in total soluble solids, titratable acidity, vitamin C and anthocyanin contents. Increased total antioxidant activity was also detected at the end of the cold storage period and was accompanied with increased total phenolic compounds. Such findings suggest that chitosan can be beneficial in extending shelf life and maintaining biochemical quality of fresh cut fruits.