Sustained release composite antimicrobial film containing oregano essential oil microcapsule for postharvest strawberry preservation

Essential oil has potential in preventing fruit rancidity and decay during storage, its limited water solubility and vulnerability to light hinder widespread application. The present study used the complex coacervation method to prepare gelatin-gum arabic (GA) microcapsules loaded with oregano essential oil, which were then incorporated into a polyvinyl alcohol substrate to construct an antimicrobial film composite (OEO@GA-PVA film). The composite film exhibited an enhanced water vapor barrier property compared to the PVA film, resulting in a reduction of the water vapor permeability (WVP) from 6.49 g·cm/(cm²·s·Pa) to 3.86 g·cm/(cm²·s·Pa). The addition of microcapsules improved the film's ability to block both UV and visible light. The OEO@GA-PVA film exhibited a sustained bacteriostatic effect and effectively prolonged the shelf life of strawberries for up to 7 days. The findings of this study can be a valuable reference for using essential oil in strawberry preservation.