Chitosan-based antioxidant films incorporated with root extract of Aralia continentalis Kitagawa for active food packaging applications

Aralia continentalis Kitagawa and ginseng are both perennial herbs of Araliaceae. The study aimed to investigate the composite packaging films with better fresh-keeping ability. The different mass concentrations of Aralia continentalis Kitagawa root extract (ARE) 0.05%, 0.10%, and 0.15% (v/w) were compounded with chitosan (CH) to make composite packaging films. Food-based composite film, its thickness, density, water contact angle (WCA), oxygen barrier properties (OP), solubility, swelling, transparency, water vapor permeability (WVP), and other physical properties, as well as tensile strength (TS), elongation at break (EAB), Young's modulus (YM), and the mechanical properties were measured, and the oxidation resistance, thermal properties, and biodegradability were also evaluated, and the structure was analyzed by infrared spectroscopy. The results showed that when the ARE content in the film was increased from 0.05 to 0.15 mg center dot mL(-1), high antioxidant capacity of the CH/ARE film was exhibited (the DPPH and ABTS(+) free radical scavenging rate was increased), and the thickness, density, swelling degree, solubility, TS, EAB, and YM of the CH/ARE composite film increased, while WCA, OP, WVP, transparency, and biodegradability were slightly reduced. We had noticed that with the increase in the ARE content, the surface microstructure in CH/ARE film changed significantly, indicating the good compatibility between CH and ARE. In summary, as a natural active substance, ARE can be combined with CH to form films, and the packaging film made can effectively improve the performance of the composite film.