Development of Alginate-Chitosan Based Coating Enriched with ZnO Nanoparticles for Increasing the Shelf Life of Orange Fruits (Citrus sinensis L.)

Edible coatings act as a protective layer surrounding fruits and vegetables, extending their shelf life. The impact of sodium alginate (SA) 1% and chitosan (CH) 0.5% layering supplemented with nano zinc oxide (ZnO) (0.50 g/L) on orange quality was investigated for 20 days at 4 °C in this study. For the test samples of oranges, the effects of coatings on quality parameters (pH, weight loss, firmness, total soluble solids, total acidity, antioxidant, ascorbic acid, respiration rate, decay rate, antioxidant enzymes, and microbiological evaluation) were examined. During the 20-day period, the coatings had a substantial impact on the quality parameters when compared to the control (non-coated oranges). Oranges with coatings had a decreased rate of change in pH, total soluble solids, and total acidity when compared to control. Oranges coated with CH + nano-ZnO had the least weight loss, firmness, ascorbic acid concentration, respiration rate, and microbial development. The CH + nano-ZnO coated samples also had the best antioxidant activity. Polyphenol oxidase and peroxidase activity were also significantly reduced, whereas, control exhibited a significant increase. According to the current study, coatings with CH + nano-ZnO can extend the shelf life of oranges by up to 20 days.