Preparation of a biodegradable chitosan packaging film based on zinc oxide, calcium chloride, nano clay and poly ethylene glycol incorporated with thyme oil for shelf-life prolongation of sweet cherry.

This study includes development of chitosan-based films with incorporated essential thyme oil and different combinations of cross-linkers viz., ZnO, CaCl2, NC, and PEG for the safe storage of sweet cherries. The resulting films stored with sweet cherries were analyzed for different physicochemical and antimicrobial properties. Incorporation of ZnO, CaCl2, NC, and PEG in chitosan-based films maintained fruit quality by conserving higher total soluble solids, titratable acidity, and reduced weight loss. The combined ZnO + CaCl2 + NC + PEG in chitosan-based films also suppressed microbial activity. The sensorial quality of fruits stored with CH + ZnO + CaCl2 + NC + PEG treatment was also stable during storage. In conclusion, the combined CH + ZnO + CaCl2 + NC + PEG with added thyme oil application is an effective approach to maintain the postharvest quality and could be an alternative to increase the shelf life of sweet cherries, besides decreasing environmental impacts of non-biodegradable packages.