title: Atmospheric cold plasma inactivation of Escherichia coli, Salmonella enterica serovar Typhimurium and Listeria monocytogenes inoculated on fresh produce.
abstract: Atmospheric cold plasma (ACP) represents a potential alternative to traditional methods for non-thermal decontamination of foods. In this study, the antimicrobial efficacy of a novel dielectric barrier discharge ACP device against Escherichia coli, Salmonella enterica Typhimurium and Listeria monocytogenes inoculated on cherry tomatoes and strawberries, was examined. Bacteria were spot inoculated on the produce surface, air dried and sealed inside a rigid polypropylene container. Samples were indirectly exposed (i.e. placed outside plasma discharge) to a high voltage (70 kVRMS) air ACP and subsequently stored at room temperature for 24 h. ACP treatment for 10, 60 and 120 s resulted in reduction of Salmonella, E. coli and L. monocytogenes populations on tomato to undetectable levels from initial populations of 3.1, 6.3, and 6.7 log10 CFU/sample, respectively. However, an extended ACP treatment time was necessary to reduce bacterial populations attached on the more complex surface of strawberries. Treatment time for 300 s resulted in reduction of E. coli, Salmonella and L. monocytogenes populations by 3.5, 3.8 and 4.2 log10 CFU/sample, respectively, and also effectively reduced the background microflora of tomatoes.
authors.affiliation: School of Food Science and Environmental Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland.
authors.forename: D
authors.initials: D
authors.lastname: Ziuzina
authors.affiliation: School of Food Science and Environmental Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland.
authors.forename: S
authors.initials: S
authors.lastname: Patil
authors.affiliation: School of Food Science and Environmental Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland; School of Chemical Engineering, University of New South Wales, Sydney, Australia.
authors.forename: P J
authors.initials: PJ
authors.lastname: Cullen
authors.affiliation: Purdue University, Nelson Hall of Food Science, West Lafayette, IN, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Keener
authors.affiliation: School of Food Science and Environmental Health, Dublin Institute of Technology, Cathal Brugha Street, Dublin 1, Ireland. Electronic address: paula.bourke@dit.ie.
authors.forename: P
authors.initials: P
authors.lastname: Bourke
mesh_terms: D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D004926:Escherichia coli / Q000737:chemistry / Q000254:growth & development*; D005519:Food Preservation / Q000295:instrumentation / Q000379:methods*; D031985:Fragaria / Q000382:microbiology*; D005638:Fruit / Q000382:microbiology*; D008089:Listeria monocytogenes / Q000737:chemistry / Q000254:growth & development*; D018551:Solanum lycopersicum / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000737:chemistry / Q000254:growth & development*
keywords: Atmospheric cold plasma; Decontamination efficacy; Fresh produce; Ozone; Pathogenic bacteria