Zein/peach gum composite antibacterial absorbent pads loaded with thirteen-spices essential oil: Preparation, characterization and its application in pork preservation

Abstract

Thirteen-spices essential oil (TSEO) is an extract derived from a blend of thirteen traditional Chinese spices “Shisan Xiang”. It has garnered significant interest for its application in meat preservation, owing to its distinctive flavor profile and potent antibacterial properties. In this study, we developed monolayer and multilayer biocomposite films composed of zein (ZN) and peach gum (PG), integrated with TSEO, utilizing a continuous casting method, to address plastic pollution and food safety by developing innovative, biodegradable packaging from food byproducts. These films were designed to function as antibacterial absorbent pads (TSEO-ZN/PG) aimed at extending the shelf life of chilled pork. The self-assembly behavior of TSEO-doped ZN within a continuous PG matrix is influenced by the casting layers. The TSEO-ZN/PG film exhibited a heterogeneous cross-sectional structure characterized by cavities that entrapped TSEO droplets and ZN microspheres. This morphology influenced swelling (2609.43 %), water vapor permeability (1.63 ± 0.23), and TSEO retention-release behavior. By adjusting the ZN/PG ratio in the intermediate layer, the films demonstrated enhanced resistance to breakage (8.969 ± 0.744 %) and thermal stability (285.00 °C). Furthermore, these films significantly impeded the proliferation of Staphylococcus aureus (53.13 %) and Escherichia coli (72.64 %). An extended shelf life of 2 days was observed in the preservation test of chilled pork characterized by significantly lower TVC, pH, and color changes compared to the control. The TSEO-ZN/PG absorbent pads developed in this study exhibited antimicrobial and adsorption properties that potentially enhance the storage quality of chilled pork.