Hydrophobic-Enhanced HPMC/Chitosan/Beeswax Edible Coatings Incorporating Fruit and Vegetable Polyphenol Extracts for Mango Fruit Preservation

Abstract

Edible coatings play a crucial part in preventing fruit decay and extending their shelf life. However, a significant volume of water will collect on the fruit's surface due to respiratory metabolism during storage, causing the covering to disintegrate. Therefore, water-resistant coating is synthesized using hydroxypropyl methylcellulose, chitosan, and the hydrophobic nature of beeswax to preserve mango fruit. In this way, three types of edible coatings that consisted of hydroxypropyl methylcellulose, chitosan, and beeswax (HCB) were made by mixing the polyphenol extracts of orange peels (OPEs), apple peels (APEs), and spinach leaves (SPEs), respectively, which were named HCB-OPE, HCB-APE, and HCB-SPE. The prepared edible coatings were found to be stable and compatible, as determined by a Zetasizer, zeta potential, Fourier transform infrared (FTIR), atomic force microscopy, and antimicrobial analysis. Furthermore, the quality parameters of the applied coatings showed promising results on mango fruit during a 13-day storage period. The HCB-OPE coating was the most active at a dose of 50 mg against Escherichia coli, with inhibition zones of 32.50 ± 7.83, and HCB-APE with 50 mg inhibited against Staphylococcus aureus by 29.56 ± 5.64 mm, respectively. The HCB-OPE coating showed a low weight loss of 1.20% ± 0.02% to 6.80% ± 0.06%. The coated mango fruits with HCB-OPE emulsion showed the lowest respiration rate (25.2 ± 0.6 mg CO2/kg/h).