Characterization of Active Biodegradable Films Based on Proso Millet Starch and Curcumin

Abstract

Starch extracted from proso millet (PMS) is used as a base material for preparing biodegradable films and curcumin is added to endow antioxidant properties to the films. The effect of various concentrations (0%, 0.5%, 1%, 2%, and 3%) of curcumin on the properties of the PMS films is reported. As the concentration of curcumin increases, tensile strength decreases and elongation at break increases. Although thermal stability of the PMS film is not improved by the addition of curcumin, water and UV–visible light barrier properties are enhanced. Moreover, the antioxidant properties of the PMS films with curcumin are enhanced with increasing curcumin content. In particular, the scavenging activities of the 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) and 2,2‐diphenyl‐1‐picrylhydrazyl radicals in the PMS film containing 3% curcumin are 100% and 42.96%, respectively. A migration test is carried out on the films for 7 days; phenolic compounds migrate faster in water than in 95% ethanol medium. These results imply that the PMS films containing curcumin can be used as new active packaging materials.