Plasma-Treated Air and Water—Assessment of Synergistic Antimicrobial Effects for Sanitation of Food Processing Surfaces and Environment

Authors

Uta Schnabel, Technological University Dublin
Oliver Handorf, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Kateryna Yarova, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Björn Zessin, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Susann Zechlin, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Diana Sydow, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Elke Zellmer, University of Greifswald, Walter-Rathenau-Straße Greifswald, Germany
Jörg Stachowiak, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Mathias Andrasch, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany
Harald Below, University of Greifswald, Walter-Rathenau-Straße Greifswald, Germany
Jörg Ehlbeck, Leibniz Institute for Plasma Science and Technology, Greifswald, Germany

Document Type

Article

Disciplines

1.4 CHEMICAL SCIENCES

Publication Details

Foods 2019, 8, 55; doi:10.3390/foods8020055

Abstract

The synergistic antimicrobial effects of plasma-processed air (PPA) and plasma-treated water (PTW), which are indirectly generated by a microwave-induced non-atmospheric pressure plasma, were investigated with the aid of proliferation assays. For this purpose, microorganisms (Listeriamonocytogenes, Escherichiacoli, Pectobacteriumcarotovorum, sporulatedBacillusatrophaeus) were cultivated as monocultures on specimens with polymeric surface structures. Both the distinct and synergistic antimicrobial potential of PPA and PTW were governed by the plasma-on time (5–50 s) and the treatment time of the specimens with PPA/PTW (1–5 min). In single PTW treatment of the bacteria, an elevation of the reduction factor with increasing treatment time could be observed (e.g., reduction factor of 2.4 to 3.0 for P. carotovorum). In comparison, the combination of PTW and subsequent PPA treatment leads to synergistic effects that are clearly not induced by longer treatment times. These findings have been valid for all bacteria (L. monocytogenes > P. carotovorum = E. coli). Controversially, the effect is reversed for endospores of B. atrophaeus. With pure PPA treatment, a strong inactivation at 50 s plasma-on time is detectable, whereas single PTW treatment shows no effect even with increasing treatment parameters. The use of synergistic effects of PTW for cleaning and PPA for drying shows a clear alternative for currently used sanitation methods in production plants. Highlights: Non-thermal atmospheric pressure microwave plasma source used indirect in two different modes—gaseous and liquid; Measurement of short and long-living nitrite and nitrate in corrosive gas PPA (plasma-processed air) and complex liquid PTW (plasma-treated water); Application of PTW and PPA in single and combined use for biological decontamination of different microorganisms.

DOI

https://doi.org/10.3390/foods8020055

Recommended Citation

Schnabel , U. et al (2019) Plasma-Treated Air and Water—Assessment of Synergistic Antimicrobial Effects for Sanitation of Food Processing Surfaces and Environment, Foods 2019, 8, 55; doi:10.3390/foods8020055