A sustained-release antibacterial gelatin hydrogel based on metal-phenolic networks for long-term preservation of...

Antibacterial hydrogel packaging often adheres poorly to hydrophobic prefabricated meat surfaces. Metal-polyphenol networks, combining metal ion antibacterial properties with polyphenol adhesion, offer promising preservation potential. In this study, tannic acid -Fe^III metal polyphenol network-coated gallic acid -loaded ovalbumin/chitosan nanoparticles with adhesion and sustainable antibacterial properties were prepared and embedded into the gelatin hydrogel to elongate the shelf life of prefabricated meat. The composite hydrogel exhibited high adhesion, with an average adhesion force of 1.4-fold ∼1.9-fold larger than the other groups. It also exhibited good antibacterial properties, the colony-forming units (CFU) of 4 type of bacteria was reduced by 0.69, 0.34, 1.05 and 0.90 log₁₀ (CFU/mL). The composite hydrogel delayed pH, total volatile basic nitrogen (TVB-N), microorganism growth, and the marginally acceptable limit was delayed by 4 days compared with the other groups in applications. These results demonstrate the composite hydrogel's significant potential as a preservation material for prefabricated meat.