Development of environment-friendly bio-based film with improved performance for food preservation using dialdehyde starch grafted konjac flour.

Abstract

Developing environment-friendly films by utilizing renewable bio-resource materials to substitute petroleum-based ones is regarded as an effective approach for addressing white pollution and its associated hazards. In this work, a redox system consisting of ascorbic acid/hydrogen peroxide (AA/H₂O₂) was established to promote the graft copolymerization of konjac flour (KF) and dialdehyde starch (DAS) for the preparation of bio-based films. The results indicated that the overall performance of the film was significantly improved after grafting DAS onto KF. Specifically, when the DAS content was 25 % of the KF weight, the film presented the optimal properties: a moisture content of 10.2 %, a water contact angle of 87.17°, a tensile strength of 33.08 MPa and a biodegradation rate of 93.16 %. Additionally, the weight loss of banana in a 7-day experiment was only 15.67 %, taking the film as a preservative material. Meanwhile, the film's dense and uniform structure also enhances its thermal properties.