Antimicrobial effectiveness of chitosan-essential oil coated plastic films against foodborne pathogens

In this study, antimicrobial efficacy of polypropylene (PP) films coated with chitosan solutions (2% wt/v) and chitosan solutions enriched with essential oils (EOs) against Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli O157:H7 were evaluated on Kashar cheese slices. Oregano and clove oils were incorporated into film solutions at 1% (v/v). Inoculated cheese samples were wrapped with films and stored at 4 degrees C for 14 days. Antimicrobial effectiveness of films against each of three pathogens was measured by plate counts performed on 1, 7, and 14 days of storage. It was found that the antimicrobial effectiveness of all film types against three pathogens were statistically significant (p < 0.05), with films containing oregano oil showed greater antimicrobial effect on pathogens than films containing clove oil. Results suggest that chitosan is an ideal biopolymer for coating onto PP films, and EOs have the potential to be used in antimicrobial coated plastic film prepared from biopolymers.