ARS | Publication request: Allspice, garlic, and oregano plant essential oils in tomato films inactive the foodborne pathogens Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes

Submitted to: Annual Meeting of the Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: February 11, 2009
Publication Date: N/A

Technical Abstract: Edible films containing plant essential oils are gaining importance as potential antibacterial formulations to extend product shelf-life and reduce risk of pathogen growth on food surfaces. An evaluation of both antimicrobial and physicochemical properties of edible films is important for applications to food systems. The main objective of the present study was to evaluate physical properties and antimicrobial activities against Escherichia coli O157:H7, Salmonella enterica and Listeria monocytogenes of tomato films with added allspice, garlic, and oregano oils (0.5-3.0% w/w in film-forming solutions). Antimicrobial activities were determined by overlay of the film on top of the bacteria and by vapor phase diffusion of the antimicrobial from the film onto the bacteria. Activities against E. coli O157:H7 and S. enterica were in the following order: oregano > allspice > garlic oils. Garlic oil was the most effective against L. monocytogenes, even at a concentration of 0.5%. L. monocytogenes bacteria were less resistant to inactivation than were E. coli. The presence of plant essential oil antimicrobials reduced the water vapor permeability of the tomato films. The results of the present study show that some essential oils in a tomato film matrix possess good physical and antimicrobial properties for food applications.