Comprehensive study on Malus ‘Donald Wyman’ crabapple extract: Its characterization, impact on chitosan film properties, and preservation efficacy in grapes

This study developed a chitosan film blended with Malus ‘Donald Wyman’ crabapple ethanol extracts for grape preservation. Antioxidant activity and phenolic composition of extracts collected in October (MEO) and March (MEM) were comparatively analyzed using UV Spectrophotometry and UPLC-MS. The MEO demonstrated superior antioxidant capacity and diverse phenolic profile attributed to higher content of phenolics (84.5 mg GA/g dw). The chitosan-MEO film underwent physicochemical evaluations, including SEM, FTIR, XRD, and TGA, to ascertain its microstructure, molecular interactions, crystallinity, and thermal stability. Mechanical testing revealed reductions in film's tensile strength and elongation at break from 13.52 MPa and 104.5% of CH film to 4.44 MPa and 31.89% of CH-MEO film, respectively, which was also evident in SEM, showing cracks in the cross-section and voids on the surface. The film effectively maintained grape quality by minimizing weight loss at 15.90% and preserving firmness at 1.88 N, total soluble solids at 11.80%, and titratable acidity at 0.89% in CH-MEO group. It also protected grapes from oxidative damage by decreasing lipid peroxidation and enhancing overall antioxidant capacity. The study underscores the potential of seasonally derived natural extracts in fortifying biocomposite films for active food packaging, thereby extending shelf-life and maintaining quality of fresh produce. • Antioxidant and phenolics of crabapple extract exhibit significant seasonal variation • Mixture of MEO to chitosan film improved its physical and physicochemical properties • Chitosan film containing MEO delays loss of physicochemical properties and antioxidant • The incorporation of MEO enhanced the preservative effect of chitosan film on grapes