Fabrication of ZnO nanoparticles reinforced PHB/PEG nanocomposite film for active packaging of Indian gooseberry and bread

Abstract

Nanocomposite films are rapidly evolving into the material choice for food packaging owing to their exceptional mechanical, thermal, and barrier qualities. This research investigates the development of novel poly(3-hydroxybutyrate) (PHB) nanocomposite film blended with polyethylene glycol (PEG) and biogenic zinc oxide nanoparticles (ZnO NPs) for active food packaging. The solvent-cast films including neat PHB, PHB/PEG, and PHB/PEG/ZnO NPs, were characterized for its structural, mechanical, thermal, and antimicrobial properties. The incorporation of PEG into the PHB matrix resulted in notable enhancement of mechanical strength and barrier performance, primarily due to the increased hydrophilicity and the plasticizing effect of PEG, which facilitated greater polymer chain mobility and flexibility. PEG also accelerated biodegradation by enhancing moisture uptake and enzymatic accessibility, thereby improving the composite's environmental sustainability. Notably, the ZnO NPs incorporated PHB/PEG film exhibited effective antimicrobial activity against various food-borne pathogens. Moreover, shelf life of bread and Indian gooseberry was extended devoid of microbial spoilage by 10 and 21 days, respectively. In the case of Indian gooseberry, important quality parameters such as pH, weight, texture, and nutritional content were effectively maintained throughout the storage period. These findings underscore the potential of PHB/PEG/ZnO NPs nanocomposite films as sustainable, biodegradable, and functional materials for active food packaging solutions, addressing both food safety and environmental concerns.

Graphical abstract