Development of antioxidant and antimicrobial packaging films based on chitosan and mangosteen (Garcinia mangostana L.) rind powder.

Mangosteen (Garcinia mangostana L.) rind has long been used as traditional medicine in Southeast Asian countries. Due to the presence of abundant polyphenols, mangosteen rind possesses potent antioxidant and antibacterial ability. In this study, mangosteen rind powder (MRP) was incorporated into chitosan (CS) film to develop active packaging for the first time. The structure, physical and functional properties of CS-MRP films containing different MRP contents (2.5, 5 and 10 wt% on CS basis) were determined. Fourier transform infrared spectroscopy revealed that the polyphenols in MRP could interact with CS through intermolecular hydrogen bonds. X-ray diffraction analysis showed the crystallinity of CS-MRP films was higher than that of CS film. Notably, MRP incorporation significantly increased the thickness, tensile strength, and UV-visible light barrier, antioxidant and antibacterial properties of CS film. However, the moisture content, water solubility, water vapor barrier ability and elongation at break of CS film were reduced by MRP incorporation. Moreover, CS-MRP film packaging effectively inhibited the increase in the peroxide value and thiobarbituric acid reactive substances of soybean oil during storage. Our results suggested CS-MRP films could be used as active packaging to increase the oxidative stability of soybean oil in food industry.