Naslov
Liquid‐phase electrical discharge plasmas for inactivation of Escherichia coli and Listeria monocytogenes

Autori
Vukušić, Tomislava ; Herceg, Zoran ; Rogers, Shane ; Mededovic Thagard, Selma

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, ostalo

Izvornik
Sustainable innovation based on science and applied research of nonthermal technologies PROCEEDINGS Editors Petros Taoukis Nikolaos Stoforos Eleni Gogou ATHENS, GREECE 2015 / Taoukis, Petros ; Stoforos, Nikolaos ; Gogou, Eleni - Atena, 2015

ISBN
978-618-82196-2-5

Skup
2015 International Nonthermal Processing Workshop,

Mjesto i datum
Atena, Grčka, 12.11.2015. - 13.11.2015

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
plasma; sterilization; water

Sažetak
The aim of this work is the development of an energy efficient and effective food sterilization technology applicable to the liquid foods manufacturing sector. We have developed an energy efficient plasma‐based process that can achieve 5‐log or greater reduction of food spoilage organisms Escherichia coli and Listeria monocytogenes in water. The technology, which creates plasma directly in a liquid, sterilizes microorganisms by combinations of chemical (hydrogen peroxide and oxidative oxygenated species), physical (shockwaves and UV light) and electrical effects. Aqueous suspensions of pure cultures of Escherichia coli (ATCC 700891) and Listeria monocytogenes were treated with direct‐in‐ liquid electrical discharge plasmas using point‐to‐plate electrode configuration as a function of several operational parameters such as discharge frequency, electrode material and electrode polarity. Through the manipulation of plasma chemistry, we were able to achieve 5‐log reduction in less than a minute, and have noted differences in optimal plasma chemistries for different organisms of interest. Negative polarity plasma showed the best inactivation results for both microorganisms. Escherichia coli was completely inactivated in 30 s with a discharge frequency of 120 Hz and Listeria monocytogenes in 60 s at 80 Hz. The extent of sterilization appears to be determined by the plasma discharge frequency, input power, plasma electrode material, and electrode polarity. The mechanism of sterilization involves complex interactions between chemical and electrical effects.

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

POVEZANOST RADA