Physicochemical and Antibacterial Evaluation of Poly (Vinyl Alcohol)/Guar Gum/Silver Nanocomposite Films for Food Packaging Applications

In this study, we prepared Poly (vinyl alcohol) (PVA)/Guar gum (GG) based nanocomposite films with a different weight ratio of silver nanoparticles (AgNPs) via in situ approach using GG itself as a reducing agent and PVA as a capping as well as stabilizing agent at room temperature. The in situ synthesized AgNPs in the PVA/GG matrix was confirmed by surface plasmon resonance (420–450 nm) and SEM-EDAX analysis. The average size of AgNPs was found to be 10 nm determined by XRD. The light transmittance is greatly influenced by the AgNPs. At an optimal concentration of AgNPs (6.8 mg), PVA/GG/Ag nanocomposite films showed improved tensile properties (Ts—23.93 MPa) and the water vapor transmission rate. The incorporation of AgNPs has significantly enhanced the hydrophobicity (~ 77%) as well as the thermal stability (~ 61.39%) of the PVA/GG film. The overall migration rate of the nanocomposite films with the three food simulants was shown significantly below the permitted limit of 10 mg/dm2. Further PVA/GG/Ag nanocomposite films showed a lower soil burial degradation rate than PVA/GG film and good antibacterial properties against environmental microorganisms such as S. aureus and E. coli bacteria. The results suggest that the prepared films can be used as promising food packaging materials.