Zein film loaded with Fructus Ligustri Lucidi essential oil: Preparation, characterization and application in fresh-cut apple preservation

Fresh-cut fruits and vegetables are a type of convenient, ready-to-use food that offers consumers a healthy choice. However, the peeling and slicing operations make them susceptible to microbial contaminations and oxidation. In this study, zein was used as the film-forming substrate, and Fructus Ligustri Lucidi essential oil (FEO), a natural bacteriostatic agent, was incorporated into zein film to prepare a film with antibacterial and antioxidant properties to prolong the shelf life of fresh-cut fruits and vegetables. Polyethylene glycol 400 (PEG400) and glucose were used as plasticizers, and the optimal formulation of the film (FZF) was obtained by orthogonal experiment: 10% PEG400, 5% glucose and 10% FEO. The films were characterized by scanning electron microscope (SEM), Fourier transform infrared spectrum (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA), and the influence of FEO on the physical, chemical, and biological characteristics of the films was explored. The results demonstrated that FEO was successfully loaded into zein film and distributed evenly. The FZF film exhibited excellent antioxidant activity, when the concentration of FEO was 200 mu g/mL, the scavenging rate of DPPH and ABTS was 81.63 +/- 0.69% and 91.44 +/- 0.55% respectively. Furthermore, the FZF film showed antibacterial properties against Staphylococcus aureus (S. S. aureus) ) and Escherichia coli (E. E. coli) ) and low cytotoxicity in vitro. . Moreover, the FZF film demonstrated anti-browning capabilities, effectively prolonging the shelf life of fresh-cut apple slices. Thus, the FZF film possesses considerable potential for utilization in food packaging.