Preparation and properties of biodegradable films made of cationic potato-peel starch and loaded with curcumin

The purpose of this study was to develop biodegradable films made of cationic potato starch-derivatives and loaded with curcumin. Potato starch was recovered from potato peel waste (PW). Cationic starch (CS) was obtained by modifying potato starch, mixed with curcumin and used to prepare composite films. Curcumin at low concentration was compatible with CS and was uniformly distributed in the CS matrix of the composite films. Compared with the pure cationic starch film, the incorporation of 5% curcumin increased the elongation at break (18%) and hydrogen-bonding interactions and reduced the water-vapor permeability (WVP) (21%) of the CS films. In addition, the mechanical properties of CS films were slightly improved, whereas the thermal stability of the CS films was unchanged. The CS/curcumin films showed excellent ultraviolet (UV) barrier performance and the addition of 5% of curcumin improved the UV blocking effect by 53.33%, but reduced the transparency by 47.74%. The composite films also had good antioxidant activity and the highest scavenging activity of DPPH and ABTS was 86.77% and 98.09% in the composite film containing 5% curcumin, and curcumin was rapidly released. In conclusion, this study shows that CS/curcumin composite films are potential bioactive packaging material for foods and can alleviate the problem of agricultural waste disposal. • The active biodegradable CS/curcumin composite film was prepared by solution casting method. • The addition of curcumin improved the UV barrier and mechanical properties of CS films. • The addition of curcumin improved the water vapor barrier and surface hydrophobicity of CS films. • The CS/curcumin composite films showed strong antioxidant activity. • The composite film had potential application value in the field of food packaging.