Preparation of Microencapsulated Composite-Modified Pickering Emulsion Coating and Its Application in Post-harvest Preservation of Cherry Tomatoes

In this study, β-cyclodextrin-encapsulated navel orange essential oil (NOEO) microcapsules were integrated into a chitosan (CS)/zein-stabilized Pickering emulsion. This formed an edible composite coating with dual sustained-release functionality. It is worth noting, in order to improve the antibacterial and antioxidant properties of chitosan, p-coumaric acid (PCA) was grafted onto chitosan. Fourier transform infrared spectroscopy confirmed successful PCA grafting onto chitosan. Hydrogen bonding potentially existed among coating components. Scanning electron microscopy verified NOEO's stable presence within the composite film. The NOEO emulsion exhibited a 4.8 μm average particle size with excellent physical stability. Compared to pure CS coating, the composite coating demonstrated a 30.3% improvement in waterproof performance. Antibacterial inhibition diameters reached 14.3 mm against both Escherichia coli and Staphylococcus aureus, and 15.3 mm against Alternaria alternata. Antioxidant capacity increased to 88.2%. Sustained-release experiments showed microcapsules enhanced essential oil release efficiency by 31%. Applied to cherry tomatoes, the coating effectively delayed senescence and decay while maintaining product quality during 16-day storage at 25 °C.The composite coating material developed in this study exhibits dual advantages of environmental benignity and economic feasibility, demonstrating promising potential for applications in postharvest quality maintenance of horticultural produce.