Recent Advances in Plasma Technology: Influence of Atmospheric Cold Plasma on Spore Inactivation

Availability of safe and pathogen-free food is becoming more critical due to difficulties in removing spores and spore-forming microorganisms from the food products. Spore-forming organisms, when exposed to industrial treatments (osmosis, desiccation, cold, heat, bases, and acid, etc.) on a long-term basis, become resistant. While traditional spore removal practices are making it extra challenging for the food industry. Recently, dielectric barrier discharge (DBD) based atmospheric cold plasma (ACP), as an emerging food preservation technology is a novel and promising plasma technology (a non-destructive preservation technology) that is potentially able to be applied in the food industry. In this context, the present study is an overview of the recent progress in the field of ACP application, and its impact on spores inactivation, physicochemical, and sensory attributes of food products, followed by the discussion on the plasma sources included corona discharge system, glow plasma under atmospheric pressure, atmospheric pressure plasma jet, resistive barrier discharge system, gliding arc discharge, DBD along with its bactericidal activities. The study will also address the impact of various process-parameters, mainly electrode type (plasma exposure direct or indirect), plasma power (voltage), treatment time, plasma-induced dose, sample distance between electrodes, and the plasma gas on the bacteriostatic efficiency. Besides, the interaction of plasma-induced reactive species with spore inactivation, deterioration mechanisms will also discuss in detail. Conclusively, the potential application of plasma technology in the food industry and its limitation with mutagenic risks or genetic toxicology will be described.