Development of Chitosan Silver Nanobiocomposites for Antimicrobial Food Packaging Applications

Abstract

Aim: This study developed and evaluated chitosan–silver nanobiocomposite films for antimicrobial food-packaging applications. Methodology: Chitosan obtained from shrimp shell waste was used as the biopolymer matrix, and silver nanoparticles (AgNPs) were incorporated at 6 wt.% and 15 wt.% through in situ synthesis followed by solution casting. The films were characterised using UV–visible spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy. Bread and fresh meat samples were packaged with the developed films, and microbial loads were monitored during five days of storage. Results: UV–visible spectra showed a characteristic surface plasmon resonance band at approximately 410–420 nm, indicating successful AgNP formation. FTIR analysis showed interactions between AgNPs and amino and hydroxyl groups in chitosan, while SEM observations indicated more uniform nanoparticle dispersion at lower AgNP loading and increased surface roughness at higher loading. In the food-packaging test, chitosan–AgNP films reduced microbial growth compared with untreated controls. By day 5, bread packaged with the nanobiocomposite film showed 1.0 × 10⁵ CFU compared with 3.0 × 10⁶ CFU in the control, while meat showed 1.5 × 10⁵ CFU compared with 3.0 × 10⁶ CFU in the control. Conclusion: The results indicate that chitosan–AgNP films can suppress microbial proliferation in bread and meat models and may be suitable for further development as biodegradable active packaging materials.