Development of starch-based films with enhanced hydrophobicity and antimicrobial activity by incorporating alkyl ketene dimers and chitosan for mango preservation

Using hydrophobic antimicrobial food packaging films offers significant opportunities to extend the shelf life of food. This study developed a hydrophobically modified starch-based film incorporating alkyl ketene dimers (AKDs) and chitosan (CS) for mango preservation. The film's physicochemical properties and structural characteristics were comprehensively analyzed. The successful integration of AKDs into the starch (ST) matrix was confirmed through FT-IR, XRD, XPS, and SEM techniques, which revealed the establishment of β-ketoester linkages via esterification. The addition of AKDs significantly enhanced the film's hydrophobicity and mechanical properties, attributed to chemical cross-linking and the formation of intermolecular hydrogen bonds. In an eight-day room temperature storage test, the ST-AKD/CS films effectively extended the shelf life of mangoes by four days compared to the control and ST groups. As all components of the films are environmentally friendly and biodegradable, these hydrophobic films offer a promising solution for prolonging the freshness of mangoes while maintaining sustainability. [Display omitted] •Water sensitivity of starch film was reduced by AKD though esterification.•Both hydrophobic groups and surface behaviors contribute to hydrophobic properties.•AKD-modified starch-based film effectively extends mango shelf life.•AKD-modified starch-based films have great potential as fruit preservation materials.