Structure, physical and antioxidant properties of chitosan-gum arabic edible films incorporated with cinnamon essential oil.

Active films based on chitosan (CS) and gum arabic (GA) incorporated with cinnamon essential oil (CEO) have been developed, and the effect of CS/GA ratios on the film structure, physical and antioxidant properties were investigated. Possible interactions among CS, GA and CEO was evaluated using rheological studies, Fourier transform infrared Spectroscopy (FT-IR) and X-ray diffraction (XRD). These results showed that there existed electrostatic interactions between CS and GA, which led to the formation of entangled structure. The addition of GA enhanced the water barrier properties of films, while it became less resistant to breakage and stretching. Confocal laser scanning microscopy (CLSM) results confirmed the higher CEO retention in films. Greatly enhanced antioxidant effectiveness were observed when the ratio of CS/GA changed from 1:0 to 1:2. However, when the ratio reached 1:4, the antioxidant capacity quickly decreased, which could be attributed to the negative influence of maximal interactions between CS and GA, leading to the loss of CEOs.