Composite chitosan films prepared using nisin and Perilla frutescense essential oil and their use to extend strawberry shelf life

The growing demand for bio-based materials for food packaging has stimulated the development of new environment-friendly films. The antibacterial films were prepared by adding nisin and different concentrations of Perilla essential oil (EO) to N-succinyl chitosan (NSC). Scanning electron microscopy, Fourier transform infrared spectrum, X-ray diffraction measurements and thermo stability analysis showed that nisin and EO dispersed in the NSC matrix. In addition, the composite films with nisin (N) and different concentrations of EO (EOx-NNSC) had good antioxidant and antibacterial activity against Staphylococcus aureus, Escherichia coli, Salmonella enteritidis and Pseudomonas tolaasii and were safe for use. Adding nisin and EO also improved the mechanical, water vapor barrier and optical properties of the films. The application of films to strawberries showed that the addition of N and EO to NSC films delayed the rapid decay of strawberries during storage. In conclusion, EOx-NNSC films can be used as a biodegradable and environment-friendly packaging material for food preservation.