Zinc oxide nanoparticles and their nanocomposites as an imperative coating for smart food packaging

The application of nanotechnology to food packaging has brought significant benefits through improved physical, gas and thermal properties. In particular, zinc oxide nanoparticles (ZnO NPs) have a substantial impact on packaging due to their exceptional antimicrobial properties, biocompatibility and biodegradability. Despite their remarkable antimicrobial and physicochemical properties, ZnO NPs may exhibit limitations in certain aspects of food packaging applications, such as water vapor permeability and mechanical strength. This review aims to investigate the integration of ZnO NPs with various polymers to develop bio nanocomposites that offer superior mechanical, thermal and antibacterial properties for food packaging. This review discusses the synthesis and integration of ZnO NPs with polymers such as starch, chitosan, gelatin, alginate, carrageenan, polylactic acid and polyvinyl. In addition, the mechanical properties, thermal stability and antibacterial activity of the nanocomposites were assessed. The absorption of ZnO NPs in the biopolymer matrix significantly increased the tensile strength, load strength, elasticity, perforation resistance, stretching to fracture resistance, durability, temperature stability and antibacterial properties of the nanocomposites. In conclusion, the integration of ZnO NPs with different polymer matrices provides an effective and environmentally friendly alternative to food packaging, thereby prolonging shelf life and reducing toxicity.