Development of Microcapsule Bioactive Paper Loaded with Chinese Fir Essential Oil to Improve the Quality of Strawberries
Essential oils are natural antibacterial substances and have potential value for application in fruit and vegetable packaging. In this study, Chinese fir essential oil (CFEO) was microencapsulated to prepare food packaging materials for the first time to overcome its volatilization and oxidation shortcomings and to obtain a sustained-release form of the oil. CFEO was effectively encapsulated in gelatin and chitosan using the complex coacervation method, and the encapsulation efficiency, microstructure, infrared spectrum and thermal stability of the microcapsules were evaluated. Experiments confirmed that the microcapsules had some antibacterial activity. A bioactive paper was developed by combining CFEO microcapsules (CFEO-Ms) with paper-based material using the film-forming property of polyvinyl alcohol (PVA). The coated paper showed good mechanical, air permeability and moisture permeability properties. Environmental scanning electron microscopy confirmed that CFEO-Ms bonded well with PVA and was successfully introduced into the paper fiber after coating, forming an obvious coating film on the surface to facilitate the continuous release of CFEO. The shelf life of strawberries was significantly prolonged when the PVA-coated paper mixed with 3% CFEO-Ms was used for packaging. The results demonstrated that the CFEO-Ms coated paper has the potential to become an effective packaging material for the preservation of strawberries.