Light-responsive anthocyanin-Fe(III) self-assembled nanoparticles for improving the performance of cellulose films and preservation of cooked meat.

Active meat preservation film is limited by passive, slow-release sterilization, requiring the development of new materials for controllable sterilization in cooked meat preservation. This study proposed the procyanidin-Fe3+ nanoparticles (PCFs) with photothermal-driven high-efficiency sterilization and antioxidant activity (Escherichia coli/Staphylococcus aureus inhibition rate > 99.99%, DPPH scavenging rate 87.83% ± 1.39%). Furthermore, the PCFs were introduced into a sodium carboxymethyl cellulose (CMC) matrix to prepare the composite films (CMC-PCFs). The PCFs modified the physical cross-linking of the CMC films through hydrogen bonds. The CMC-PCF0.6 formulation with the PCF content of 0.6% maximally enhanced the film's thermal stability, water solubility (dissolution rate: 24.52% ± 1.49%), and mechanical strength (tensile strength: 30.26 ± 0.10 MPa, elongation at break: 10.75 ± 0.47%, elastic modulus: 1095.82 ± 28.21 MPa, toughness: 2.6 ± 0.11 MJ/m2). Under 808 nm laser, CMC-PCFs obviously reduced the TVB-N of pork by 52.10%, inhibited 99.08% of bacteria, maintained pH below 6.7, and delayed spoilage during 4-day storage. The photothermal sterilization with on-demand enhancement ability can meet the specific sterilization requirements during the microbial outbreak period in the storage of cooked meat products. This provides a safe and controllable method to replace traditional preservation technologies and alleviate global meat waste issues.