Enhanced Functional Properties of Chitosan Films Incorporated With Proanthocyanidins/Cinnamaldehyde/γ-Cyclodextrin Microcapsules for Citrus Fruit Preservation

To address the demand for sustainable postharvest preservation, this study developed a chitosan-based composite film integrated with γ -cyclodextrin ( γ -CD) microcapsules encapsulating proanthocyanidins and cinnamaldehyde. The primary objectives were to evaluate the film’s physicochemical properties and assess its efficacy in mitigating quality deterioration in citrus fruits during storage. Results demonstrated that the composite film significantly reduced weight loss (5.78%), maintained firmness (≥ 80% retention), and delayed changes in total soluble solids (TSSs) and pH compared to uncoated controls. Furthermore, it inhibited vitamin C degradation (≤ 35% loss) and extended shelf life to 40 days at 15°C by suppressing microbial growth and oxidative stress. The synergistic effects of chitosan’s film-forming capacity and the sustained release of bioactive compounds from γ -CD microcapsules, among which proanthocyanidins had good antioxidant function and cinnamaldehyde had good antibacterial property, played a key role in the preservation of citrus fruits.