Optimized chitosan edible coating for guava and its characterization

Abstract

Using the Response surface methodology (RSM), the impact of composite edible films (chitosan, tween 80) on the shelf life of guava (Psidium guajava) kept at temperature 20 ± 2 °C and 55 ± 2 % relative humidity (RH) was assessed. To determine the best possible combination, a total of 13 edible coating formulations including tween 80 (0–2 % w/v) and chitosan (0.5–2.5 %, w/v) were examined. Quality criteria such as physiological loss in weight, total soluble solids, ascorbic acid, antioxidant activity and titratable acidity of the edible coated guava were selected as response variables for optimization. It was shown that the concentration of chitosan and tween 80 in the formulation had the greatest impact on the response variables. The most effective edible coating for guava fruit was discovered to consist of chitosan 2.50 % and Tween 80 2 %; the predicted values of the response variables were ascorbic acid 232.79 mg/100 g, firmness 14.87 N, total soluble solids 5.07 °B, titratable acidity 5.75 %, and physiological weight loss 3.11 %. This study suggests that chitosan coating effectively prolongs the quality attributes of guava fruits after harvesting due to maintain firmness, ascorbic acid, and minimum loss in weight during storage. In conclusion, the innovative application of Response Surface Methodology (RSM) in this study has unveiled a powerful strategy for optimizing composite edible films, specifically chitosan and Tween 80, to significantly enhance the shelf life of guava fruits. Through meticulous exploration of 13 coating formulations, our findings underscore the pivotal role of chitosan and Tween 80 concentrations in influencing key quality parameters, including physiological loss in weight, total soluble solids, ascorbic acid, antioxidant activity, and titratable acidity.