Fabrication of cinnamaldehyde–shellac nanoparticle-filled chitosan packaging material and application in chilled beef preservation

BACKGROUND Cinnamaldehyde (CA) is the main functional component of cinnamon essential oil, exhibits strong anti-microbial activity and safety. Shellac (SHL) nanoparticles enable the encapsulation and controlled release of CA while improving the physiochemical properties of chitosan (CS) films. To strengthen the anti-bacterial activity of SHL–CS films, CA–SHL nanoparticles were prepared by an anti-solvent precipitation method with Tween 80 as surfactant, and subsequently incorporated into CS film-forming solution. The resulting CA–SHL nanoparticle-filled CS coatings were then applied for the preservation of chilled beef. RESULTS The particle size of CA–SHL nanoparticles showed a unimodal distribution, decreasing with higher SHL content or lower CA concentration. Stable CA–SHL nanoparticles had relatively low zeta-potential values, indicating the stabilization effect of Tween 80. Incorporation of CA–SHL nanoparticles into CS films improved UV barrier properties, reduced water vapor permeability, improved pH corrosion resistance, and strengthened anti-bacterial activity. The CA–SHL nanoparticle-filled CS coatings extended the shelf life of chilled beef from 4 to 8 days. CONCLUSION The enhanced properties of CA–SHL nanoparticle-filled CS composite films highlight their strong potential for food packaging and preservation. © 2025 Society of Chemical Industry.