Tea Polyphenol–Loaded Chitosan Nanoparticles Incorporated Into Carboxymethyl Cellulose/Potato Starch to Develop Sustained‐Release Bioactive Films for Pork Preservation

ABSTRACT This study aims to prepare tea polyphenol–loaded chitosan (CS‐TP) nanoparticles and incorporate them into a carboxymethyl cellulose/potato starch (CMC/S) matrix to develop an active film for pork preservation. The impacts of CS‐TP nanoparticles on the physicochemical, antioxidant and antimicrobial properties of CMC/S film were evaluated, along with the effects of composite films on pork preservation. The introduction of CS‐TP nanoparticles strengthened the mechanical strength and water vapour barrier performance of the CMC/S film while reducing its hydrophilicity. The CMC/S films containing CS‐TP nanoparticles exhibited excellent UV‐blocking and antioxidant properties, as well as strong antibacterial effects against Staphylococcus aureus and Pseudomonas aeruginosa . The in vitro release results demonstrated a sustained release of TP from the composite films, with the release kinetics fitting the Weibull model ( R 2 = 0.9742–0.9867). The release of nano‐encapsulated TP is collectively governed by surface erosion, nanostructural degradation, molecular diffusion and polymer chain relaxation. Furthermore, preservation experiments demonstrated that CMC/S films containing CS‐TP nanoparticles effectively inhibited microbial growth and oxidative deterioration in refrigerated (4°C) pork loin while preserving colour and texture properties. This eco‐friendly, sustained‐release, multifunctional material shows considerable promise for food packaging applications and provides valuable insights for designing other food preservation materials.