Advanced oxidation technology with photohydroionization as a surface treatment for controlling Listeria monocytogenes on stainless steel surfaces and ready-to-eat cheese and turkey

Foodborne Pathog Dis. 2014 Apr;11(4):295-300. doi: 10.1089/fpd.2013.1512. Epub 2014 Jan 20.

Abstract

Listeria monocytogenes is difficult to control in food and processing environments due to its widespread nature and ability to survive in a range of adverse conditions, including low temperatures, pH, and high salt concentrations. The objective of this study was to evaluate the efficacy of Photohydroionization™ (PHI; RGF Environmental Group, Inc., Riviera, Beach, FL), a novel advanced oxidation technology, as a surface treatment to control L. monocytogenes on food-contact surfaces, sliced American cheese, and ready-to-eat (RTE) turkey. A five-strain cocktail of L. monocytogenes was used to inoculate sample surfaces. Food-contact surfaces were exposed to ultraviolet and other oxidative gases produced by the PHI system for 10, 20, 30, 45, 60, and 120 s and 5, 10, and 15 min; cheese and turkey samples were treated for 30, 60, and 120 s and 5 min. For each matrix at each time point, seven samples were treated and enumerated by plating appropriate dilutions onto modified oxford medium and thin-agar-layer modified oxford medium. Results showed reductions (p<0.05) in L. monocytogenes: 4.37 log colony-forming units (CFU)/coupon on stainless steel after 15-min treatment. A 1.39 and 1.63 log CFU/sample after 120 s and 2.16 and 2.52 log CFU/sample after 5 min were seen on American cheese and ready-to-eat turkey, respectively. Lipid oxidation analyses performed on cheese and turkey samples indicated that PHI treatment did not affect (p>0.05) thiobarbituric acid-reactive substances values. This study demonstrates the efficacy of PHI treatment to reduce L. monocytogenes on stainless steel and RTE foods and may serve as a processing intervention to ensure safe production of food.

MeSH terms

  • Animals
  • Cheese / microbiology
  • Colony Count, Microbial
  • Consumer Product Safety
  • Fast Foods / microbiology
  • Food Microbiology*
  • Food-Processing Industry / methods
  • Gases / pharmacology
  • Humans
  • Hydrogen Peroxide / pharmacology
  • Listeria monocytogenes / growth & development
  • Listeria monocytogenes / radiation effects*
  • Listeriosis / microbiology
  • Listeriosis / prevention & control*
  • Oxidation-Reduction
  • Ozone / pharmacology
  • Poultry Products / microbiology*
  • Stainless Steel
  • Sterilization
  • Time Factors
  • Turkeys / microbiology
  • Ultraviolet Rays
  • Water / metabolism

Substances

  • Gases
  • Water
  • Stainless Steel
  • Ozone
  • Hydrogen Peroxide