Edible Active Coatings Based on Pectin, Pullulan, and Chitosan Increase Quality and Shelf Life of Strawberries (Fragaria ananassa)

Edible active coatings (EACs) based on pectin, pullulan, and chitosan incorporated with sodium benzoate and potassium sorbate were employed to improve the quality and shelf life of strawberries. Fruits were washed, disinfected, coated by dipping, packed, and stored at 4 degrees C for 15 d. Application of EACs reduced (P < 0.05) weight loss and fruit softening and delayed alteration of color (redness) and total soluble solids content. In contrast, pH and titratable acidity were not affected (P > 0.05) throughout storage, and ascorbic acid content was maintained in pectin-EAC coated strawberries. Microbiological analyses showed that application of EACs reduced (P < 0.05) microbial growth (total aerobic counts, molds, and yeasts) on strawberries. Chitosan-EAC coated strawberries presented the best results in microbial growth assays. Sensory quality (color, flavor, texture, and acceptance) improved and decay rate decreased (P < 0.05) in pectin-EAC, pullulan-EAC, and chitosan-EAC coated strawberries. In conclusion, EACs based on polysaccharides improved the physicochemical, microbiological, and sensory characteristics, increasing the shelf life of strawberries from 6 (control) to 15 d (coated fruits). Practical Application Consumer demands for high quality foods have led to development of technologies for preserving the quality of these products. The present work focuses on improving quality and increasing the shelf life of strawberries using edible coatings based on polysaccharides and antimicrobial agents. The results of this work are applicable to industrial food production and postharvest handling to enhance overall quality and shelf life of strawberries.