The effects of edible chitosan coating on prolonging the shelf life of green chilies (Capsicum annuum L.)

Abstract

Green chillies (Capsicum annuum L.) are susceptible to pest attack, experiences water loss rapidly in a short time and also experiences chilling injury when stored at a cool temperature that leads to shorter shelf life. Therefore, this study was conducted to examine the effects of chitosan at different concentrations (0.5%, 1.0% and 2.0%) on the shelf life of green chilies stored at ambient temperature (27°C) for 21 days. The effectiveness of the chitosan treatments in extending green chilies’ shelf-life was evaluated by determining their physical and chemical qualities. Coated green chilies are able to preserve for a longer period of time compared to uncoated green chilies. Regardless of any chitosan concentration, the total soluble solid content (TSS) of coated green chilies had increased starting from day 3 to day 21 day as compared to the control. At the highest concentration of 2.0%, chitosan treatment was able to reduce the pH by 28% on day 6 of the storage period, meanwhile, the pH was maintained across the concentration at the end of the storage period (day 21). It was found that the green chilies faced 10 to 22% weight loss across the concentration as compared to the control at the end of the storage period, where the highest weight loss was prominent at 2.0% chitosan. However, in terms of firmness, the chitosan treatments do not give any significant effect on all the treated green chilies. These results suggest that the application of edible chitosan coating contributes to lower pH and weight loss which is responsible for the longer shelf life of the green chilies.