A novel functionalized food packaging film with microwave-modified konjac glucomannan/chitosan/citric acid incorporated with antioxidant of bamboo leaves

The health hazards associated with the use of plastic films to preserve food require the development of active films from non-toxic and antioxidant rich biological sources. In this study, a novel functional food packaging material was developed by microwave modification of a composite film made of konjac glucomannan (KGM)/chitosan (CTS)/citric acid with the addition of the antioxidant of bamboo leaves (AOB). The effects of different contents of the AOB (0.1%, 0.2%, 0.3% and 0.4%, w/v) on the structure, physical properties and antioxidant activity of KGM/CTS/citric acid films were systematically studied. The results from Fourier transform infrared spectroscopy and atomic force microscopy showed that the components in the KGM/CTS/citric acid film had good compatibility due to the hydrogen bonds among them and furthermore the AOB was evenly distributed in the composite film. The addition of AOB significantly improved the oxidation resistance, anti UV–Vis and mechanical properties of the materials. Moreover, when the AOB content was 0.2%, the film had the best barrier property and the maximum elongation at break. Therefore, with all the meaningful improvement, the newly developed KGM/CTS/citric acid biological film might be used as promising food packaging materials in the future.