Composites Bioplastic Film for Various Concentration of Zinc Oxide (ZnO) Nanocrystals Towards Physical Properties for High Biodegradability in Soil and Seawater

The effect of various amount of ZnO nanocrystals (NCs) in composite starch/ZnO (PZ) and starch/chitosan/ZnO (PK) to the physical, structural, biodegradation, and antibacterial properties have been synthesized using casting method. The amount of ZnO are 3%, 6%, 10%, 13%, and 16%, and distilled water in acetic acid/glycerin/cassava starch was incorporated into gelatin films. We successfully demonstrated that, the ZnO NCs highly contributing to the crystalline phase and tensile strength of bioplastics. The highest value of tensile strength is for 13% ZnO-bioplastics which could be completely decomposed both in ordinary soil and in seawater for less than 30 days. The packaging tests revealed that an increase in microbial shelf life of sliced bread from 10 to 30 days for PZ and PK samples. All active coatings lessened the number of molds in sliced bread for 30 days, and further improvement in antimicrobial properties obtained for coatings contains 10, 13, and 16% ZnO NCs with no fungal growth for 30 days. In this study shows potential of ZnO NCs to be applied as an environmentally friendly bioplastics starch and starch/chitosan-based to improve shelf life as a food packaging.