Development of polyvinyl alcohol/chitosan/pullulan blended films incorporated with tea extract-synthesized TiO₂ nanoparticles for active food packaging.

In recent years, nanoparticle-infused biopolymeric films have emerged as promising alternatives to non-biodegradable synthetic packaging that poses significant environmental concerns. This work aims to develop and characterize biopolymeric films for food packaging applications using polyvinyl alcohol (PVA)/Chitosan (CS)/Pullulan (PL) incorporated with TiO nanoparticles (NPs) synthesized using tea leaf extract. PVA/CS/PL (1:0.5:0.5) films were developed with varying concentrations of TiO₂ NPs (0.5, 1, and 1.5 wt%), and their effects on the films' physical, thermal, transmission, mechanical and antibacterial properties were investigated. The results show that the addition of TiO NPs improve the film's thermal stability and mechanical strength. The addition of TiO NPs (<1 wt%) greatly increased the tensile strength of the bio-composite films while simultaneously lowering their gas barrier properties. However, increasing the TiO NP percentage (>1 wt%) further enhanced the film's gas barrier properties while decreasing its tensile strength. The antibacterial efficacy of these bio-composite films was confirmed by an antimicrobial assay against E. coli. These findings provide a pathway for the value-added utilization of tea extract polyphenols and highlight the potential of TiO₂-incorporated PVA/CS/PL biodegradable polymer film as a promising candidate for green food packaging applications.