Effects of Sorbic Acid‐Chitosan Microcapsules as Antimicrobial Agent on the Properties of Ethylene Vinyl Alcohol Copolymer Film for Food Packaging

Abstract This paper discusses the possibility of using sorbic acid‐chitosan microcapsules (S‐MPs) as an antibacterial component of active ethylene vinyl alcohol copolymer (EVOH) film. S‐MPs with a diameter of approximately 1 to 4 μm showed a sorbic acid loading capacity of 46.5%. Addition of S‐MPs (3%, w/w) increased the tensile strength, haze, oxygen, and water vapor barrier properties, as well as reduced the elongations at break and transmittance of S‐MPs‐EVOH (S‐MP‐EVOH) film. Antibacterial tests showed that the inhibitory capacity of S‐MP‐EVOH film against Salmonella Enteritidis and Escherichia coli was higher than that against Listeria monocytogenes . Moreover, the antibacterial effect of sorbic acid‐EVOH (S‐EVOH) film was stronger than that of S‐MP‐EVOH film. However, S‐MP‐EVOH film demonstrated a longer effective time than S‐EVOH film. Using the total viable counts and total volatile base nitrogen as the judgment standard, S‐MP‐EVOH/polyethylene terephthalate (PET) composite film could extend the shelf life of fish fillets by 4 d at 4 °C, compared with EVOH/PET film. For this reason, S‐MP could be a potential antibacterial component of active films.