An antibacterial active packaging system based on chitosan-stabilized W/O/W emulsion for the room-temperature storage of pork

Abstract This study aimed to develop a novel active coating for extending the shelf life of pork stored at 25 ± 2 °C by investigating the microstructure and preservation properties of composite emulsions based on water-in-oil-in-water (W/O/W) double emulsions (DEs) and chitosan (CS). The analysis revealed that the DEs formed an enhanced network structure with CS chains through electrostatic interactions. Fourier-transform infrared (FTIR) spectroscopy confirmed the successful encapsulation of oregano essential oil within the composite films, as well as the formation of hydrogen bonds between the DEs and CS. The composite emulsion containing 7.5% DEs demonstrated optimal viscosity. When applied as a coating on pork, the CS/DEs film effectively neutralized biogenic amines and retarded the pH increase, with the final pH value 3.82% lower than that of the control group over a 48-h period. The coating also inhibited the degradation of proteins and amino acids in the pork, which resulted in reductions of 31.23% in total volatile basic nitrogen (TVB-N) accumulation and 22.32% in total bacterial counts. In conclusion, the CS/DEs composite coating significantly extended the shelf life of pork from 12 to 48 h at room temperature, presenting a promising strategy for the room-temperature preservation of meat products. Graphical Abstract