A Green Approach to Bio-Based Active Packaging: Grape Skin Extract-Synthesized AgNPs for Food Preservation

This study aimed to develop an environmentally friendly composite film with effective antibacterial and preservation properties. Silver nanoparticles (AgNPs) were green-synthesized using grape skin extract as a natural reducing agent and incorporated into a PVA/chitosan matrix. The composition of the extract and the structural characteristics of the AgNPs were characterized by UPLC-MS and TEM. The barrier, mechanical performance, antibacterial, and fruit preservation properties of the resulting films were systematically evaluated. The results showed that the incorporation of AgNPs significantly improved the water vapor and oxygen barrier properties of the film and imparted excellent broad-spectrum antibacterial activity. In grape storage experiments, films with higher AgNPs content effectively delayed skin aging and moisture loss, maintaining better visual quality of the fruit. This work provides a green and feasible approach for the preparation of nanoparticle-enhanced antibacterial packaging materials based on natural products, with promising application potential.