Gas Permeability and Permselectivity of Poly(L-Lactic Acid)/SiO Film and Its Application in Equilibrium-Modified Atmosphere Packaging for Chilled Meat.

A layer of SiO was deposited on the surface of poly(L-lactic acid) (PLLA) film to fabricate a PLLA/SiO layered film, by plasma-enhanced chemical vapor deposition (PECVD) process. PLLA/SiO film showed Young's modulus and tensile strength increased by 119.2% and 91.6%, respectively, over those of neat PLLA film. At 5 °C, the oxygen (O ) and carbon dioxide (CO ) permeability of PLLA/SiO film decreased by 78.7% and 71.7%, respectively, and the CO /O permselectivity increased by 32.5%, compared to that of the neat PLLA film. When the PLLA/SiO film was applied to the equilibrium-modified atmosphere packaging of chilled meat, the gas composition in packaging reached a dynamic equilibrium with 6% to 11% CO and 8% to 13% O . Combined with tea polyphenol pads, which effectively inhibited the microbial growth, the desirable color of meat was maintained and an extended shelf life of 52 d was achieved for the chilled meat.