Biopolymer films incorporated with chlorogenic acid nanoparticles for active food packaging application.

Food packaging is innovating towards more environmental-friendly polymers and broader applications of bioactive compounds. In this study, active packaging materials were successfully prepared by incorporating chlorogenic acid (CGA) nanoparticles into pullulan/gelatin polymer matrixes. The rhamnolipid (RL) and/or CGA were combined with chitosan (CS) to synthesize active nanoparticles by the ionic crosslinking method. The film containing CS/RL/CGA nanoparticles (F/CRC) exhibited both ultrahigh visible light (400-760 nm) transmittance (approximately 90%) and UVA (320-400 nm)-blocking efficiency (89.06%). Its fluorescent properties can be used for anti-counterfeiting. Significantly, the bacterial inhibition rates of F/CRC against E. coli and S. aureus were 92.14% and 98.72%. F/CRC also showed good antioxidant capability and biosafety. Finally, the packaging test further indicated that F/CRC could delay the browning of bananas and the bacteria growth of chicken samples. This work presents a green and feasible route to produce functional materials with UV-shielding properties for packaging applications.