Nanoreinforcement of Pectin Film to Enhance its Functional Packaging Properties by Incorporating ZnO Nanoparticles

The main objective of this study was to enhance functional packaging properties of pectin film by using zinc oxide nanoparticles (ZnO-NPs) as nanoreinforcing agent. Pectin/ZnO bio-nanocomposite films were fabricated at 4 levels of ZnO-NPs, i.e., 0.5, 1.0, 2.0 and 5.0% (w/w). The effects of ZnO-NPs incorporation on improving the mechanical properties and water resistance of the films were investigated. ZnO-NPs were successfully incorporated into pectin films by nanodispersion technique followed by casting method. The presence of ZnO-NPs inside pectin films was observed clearly by SEM. The improvement in tensile strength could be achieved with ZnO-NPs incorporation without obvious loss in elasticity. Potential antimicrobial activity of pectin-ZnO nanocomposite films was proved in the absence of mold after exposing them at 97% RH and room temperature for 14 days, whereas the growth of mold had been observed in pure pectin film after 3 days of exposure. In terms of film transparency, the significant change in film opacity was only found in the film prepared with 5% of ZnO. Results suggested that it would be favorable to prepare pectin/ZnO nanocomposite film by using ZnO-NPs at the amount of 2% (w/w) in the future work.