Application of a Multi-Component Composite Edible Coating for the Preservation of Strawberry Fruit

Abstract

The rapid perishability of strawberries due to factors such as fungal decay, mechanical damage, and respiration significantly limits their shelf life. In this study, a novel multi-component edible coating composed of bacterial cellulose, chitosan, and gellan gum (BChG) was developed to enhance the postharvest quality and extend the shelf life of strawberries. The coated fruits were evaluated over a 15-day storage period for key parameters such as weight loss, total soluble solids (TSS), titratable acidity (TA), enzymatic activity, color retention, antioxidant activity, and microbiological analysis. The results demonstrated that coated strawberries exhibited significantly lower weight loss, reduced cellulase activity, and higher retention of TSS and TA compared to uncoated controls. The evaluation of microbial quality indicated that coatings, particularly those with higher concentrations of chitosan, control the growth of total mesophilic aerobic bacteria (TMAB) and molds and yeasts (MY), due to the antimicrobial properties of chitosan. This contributed to extending the shelf life of the fruit by preventing spoilage and reducing the risk of toxic compound formation. Additionally, the BChG coatings also preserved the characteristic red color of the fruit and maintained higher antioxidant activity, with BChG-4 being the most effective formulation. The inclusion of chitosan in the coatings was found to play a crucial role in reducing respiration, delaying ripening, and enhancing the fruit’s resistance to oxidative damage. Overall, multi-component coatings, particularly those with higher chitosan concentrations, offer a promising method for extending the shelf life of strawberries, reducing postharvest losses, and preserving fruit quality under ambient storage conditions.