Development of antioxidant and antimicrobial packaging films based on chitosan, D-α-tocopheryl polyethylene glycol 1000 succinate and silicon dioxide nanoparticles

Antioxidant and antimicrobial packaging were developed by adding D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) and/or silicon dioxide nanoparticles (nano-SiO2) into chitosan (CS) films. The microstructures, physical and functional properties of CS, CS-TPGS, CS-SiO2 and CS-TPGS-SiO2 films were compared. Results showed the simultaneous addition of TPGS and nano-SiO2 into CS film produced a compact inner microstructure and strong intermolecular hydrogen bond interactions. Meanwhile, the addition of TPGS slightly increased the crystallinity of CS-TPGS and CS-TPGS-SiO2 films. By comparing different films, CS-TPGS-SiO2 film presented the lowest moisture content, water vapor and oxygen permeability, whereas the highest tensile strength and elongation at break. Moreover, CS-TPGS and CS-TPGS-SiO2 films possessed stronger free radical scavenging activity than CS and CS-SiO2 films. CS-SiO2 and CS-TPGS-SiO2 films showed higher antimicrobial activity than CS and CS-TPGS films. Notably, CS-TPGS and CS-TPGS-SiO2 film packaging effectively increased the oxidative stability of soybean oil. Our results suggest CS-TPGS-SiO2 film can be used as a novel antioxidant and antimicrobial packaging material in food industry.