Microbial decontamination of chicken using atmospheric plasma bubbles

Abstract

In this study, we demonstrate that atmospheric air plasma bubbles are an effective, energy-efficient, residue-free alternative to current decontamination techniques. Five to fifteen minutes of plasma-bubble treatments of inoculated chicken skin led to a significant reduction in colony-forming units (CFUs). We show that the activation efficiency is dependent on the plasma discharge frequency, with a higher one (2,000 Hz) leading to a higher CFU reduction (1.4 log) as compared with a lower (0.3 log) reduction at 1,000 Hz. Scanning electron microscopy pictures of treated bacteria reveal damage to the cells. An evaluation of the physicochemical properties of the generated plasma-activated water revealed an increase in conductivity and in ozone, nitrite, nitrate, hydroxyl, and peroxide concentrations with higher frequencies, all contributing to the observed antimicrobial effect.