Ionized gas kills pathogens, study finds
Brief exposure of packaged fruits, vegetables or liquids to an electrical field may eliminate all traces of foodborne pathogens, a Purdue University study finds.
Food science professor Kevin Keener and researchers at Dublin Institute of Technology published their results in theJournal of Applied Microbiology.
The experimental method used electricity to generate a plasma, or ionized gas, from gases inside the sealed package. It created short-lived, bacteria-killing molecules such as ozone, nitrogen oxides and hydrogen peroxide.
The 20-second treatment, followed by 24 hours of exposure to the plasma, eliminated bacteria on food surfaces, according to the study. Developed commercially, the cost of such a process should be comparable to existing chemical and heat treatments, Keener said in a news release.
“Even in the most resistant bacteria-growing media, 45 seconds of treatment gave us complete elimination of the E. coli,” said Keener, who also appears in an online video.
The method could lead to a cold pasteurization process for juices and liquids, according to the researcher, and perhaps to an alternative to chlorine washes for produce.
“Chlorine water works well on hard surfaces,” Keener said in the release. “But there can be issues if bacteria get inside organic matter on the produce, making chlorine ineffective.”
Another possible application is development of portable devices to purify water in places lacking purification capacity.
The research was funded by the European Community’s Seventh Framework program. The results are part of a larger European Union project, Safe-Bag. More information is online.
Additional research is planned to consider how the process affects food quality.
The Purdue professor plus researchers from Ireland-based Dublin Institute of Technology and Dublin City University and Spain-based Innovació i Recerca Industrial i Sostenible, plan to develop a pre-commercial system for larger-scale decontamination testing.