Preparation of humidity-responsive cinnamon essential oil nanomicelles and its effect on post-harvest quality of strawberries

Abstract Biodegradable materials have attracted considerable attention to be applied in maintaining food quality and safety due to their ability of a sustained release of antimicrobial agents. In this study, cinnamon essential oil (CEO) loaded poly (ethylene glycol)-poly (ε-caprolactone) (PEG-PCL) micelles (CEO-micelles) were prepared for humidity-controlled CEO release and preservation of strawberry quality. The CEO-micelles with spherical shape and uniform size were obtained, and a high encapsulation rate (92.00 ± 1.77%) of CEO was achieved. X-ray diffraction demonstrated that the CEO was successfully encapsulated in PEG-PCL micelles. The release rate could be controlled by adjusting the relative humidity (RH) and 75% RH was favorable for CEO release from micelles (with 72% total amount release in 7 d). The encapsulation of CEO with high concentrations in PEG-PCL micelles reduced the cytotoxicity. Additionally, CEO-micelles exhibited high antifungal activity against Botrytis cinerea, the main pathogenic fungus of strawberry. Finally, the application of CEO-micelles to the preservation of strawberries had a positive effect on changes in decay rate, weight loss, firmness, color and total soluble solids.