Effects of plant essential oils and oil compounds on mechanical, barrier and antimicrobial properties of alginate–apple puree edible films

Mechanical, barrier and antimicrobial properties of 0.1–0.5% suspensions of the following essential oils (EOs)/oil compounds (OCs) were evaluated against the foodborne pathogen Escherichia coli O157:H7 in alginate–apple puree edible film (AAPEF): oregano oil/carvacrol; cinnamon oil/cinnamaldehyde; and lemongrass oil/citral. The presence of plant essential oils did not significantly affect water vapor and oxygen permeabilities of the films, but did significantly modify tensile properties. Antimicrobial activities of solutions used to prepare edible films (AAPFFS) were also determined. The results obtained demonstrate that carvacrol exhibited the strongest antimicrobial activity against E. coli O157:H7. The data show that the antimicrobial activities were in the following order: carvacrol > oregano oil > citral > lemongrass oil > cinnamaldehyde > cinnamon oil. This study showed that plant-derived essential oils and their constituents could be used to prepare apple-based antimicrobial edible films for food applications.