Characterization and antibacterial properties of chitosan–polyvinyl alcohol-3-phenyllactic acid as a biodegradable active food packaging

Abstract

Antibacterial active films based on chitosan (CS)–polyvinyl alcohol (PVA) blends enriched with 3-phenyllactic acid (3-PLA) were developed and evaluated. The CS–PVA–3-PLA films were flexible, clear, homogeneous, and smooth. The addition of 3-PLA (<1.75%) did not affect surface microstructure, thickness, color, moisture content, water solubility, and water vapor permeability of films. Nevertheless, the 3-PLA incorporation remarkably improved elongation at break, ultraviolet barrier property and thermal stability and decreased tensile strength. This indicates that the 3-PLA could interact with CS–PVA matrix, which was also observed via ATR/FTIR and XDR. Furthermore, addition of 3-PLA into the CS–PVA films effectively inhibited growth of foodborne spoilage bacteria, The release curves of 3-PLA showed that CS–PVA-3-PLA film in 95% ethanol solutions had the longest release time. These results suggest that the CS–PVA–3-PLA film is a potential antibacterial and biodegradable material for food packaging applications.