Biodegradable Chitosan Films Incorporated with β-Cyclodextrin Microcapsules Loaded Clove with Essential Oil for Table Grape Preservation
Postharvest spoilage of fresh fruits demands efficient bio-based packaging films. Here, chitosan/gelatin (CG) films were incorporated with β-cyclodextrin-encapsulated clove essential oil microcapsules (β-CD@CEO MCs) at varying loadings. The results suggested that CEO encapsulation occurred within β-CD cavities and hydrogen-bond binding of MCs to the CG matrix. At 0.4% MCs, the composite film showed 60.11% higher tensile strength, excellent UV shielding, lower water vapor transmission rate, and strong antioxidant activity (DPPH 89.6%, ABTS 97.1), along with 58.21% biodegradation after 16 days of soil burial. In vitro release studies revealed a pH-responsive sustained release profile of CEO from the composite films, with faster release under acidic conditions (98.5% at pH 3.5 after 72 h) compared to neutral conditions (87.2% at pH 7.0), indicating the potential for targeted release on the weakly acidic grape surface. The film also exhibited significant antimicrobial effects against Botrytis cinerea, Penicillium gladioli, Staphylococcus aureus, and Escherichia coli. In table grape preservation, CG/MCs-0.4 film effectively delayed decay, reduced weight loss by 38.79%, maintained firmness and color, and preserved higher levels of soluble solids, titratable acidity, reducing sugars, and vitamin C compared to polyethylene packaging and untreated controls.