Cold plasma sanitation system

Abstract

Cold plasma is a relatively new nonthermal food processing method to perform antimicrobial treatment on the surface of foods. The main antimicrobial action is due to reactive chemical species and UV light generated by the cold plasma ionization process. There are a number of different plasma sanitation systems due to various possible electrode configurations (geometry, number, location) and operating conditions. A considerable amount of research and development has occurred in recent years on systems that operate at atmospheric pressures and relatively low temperatures. Our objective was to create a cold plasma sanitation system that could batch sanitize 25 to 50 lbs. of pecans for at least two minutes at a time. The system was be designed to be both hygienic (cleanable) and compatible with current equipment. It was designed to be resistant to oxidation as well. Additionally, the distance between the pecans and the electrodes had to be adjustable to investigate optimum pathogen reduction. Finally, the system utilized trays vertically stacked next to each other in order to create vertical columns. Gravity was used to dump the pecans into the top of these columns, and after they have been processed they are released from the bottom of the system. Testing was performed at the OSU Biosystems & Agricultural Engineering Lab and at the OSU Food and Agricultural Products Center.