Non-thermal plasma technique for preservation of raw or fresh foods: A review

Abstract Fruits and vegetables, as fresh foods, are significant sources of nutrients. However, the spread of diseases related to fresh foods is widespread. Development and research of rotting-control technologies are necessary to maintain quality, reduce postharvest biological hazards, while processing and storage are essential to increase their shelf-life. Cold plasma as an advanced non-thermal disinfection method can be supplementary or sole alternative for reducing microbial loads on raw or fresh products and packaging materials. Plasma employs inert gases at room temperature, ionized and highly reactive, e.g., positive and negative ions, electrons, molecules in (non) excited states, free radicals, and photons. Different plasma species react with the biological cells, fostering permanent changes at the molecular levels and morphology, thus leading to their inactivation. There are three primary mechanisms attributed to cell death by plasma, including cell surface etching induced by reactive species, formed during plasma generation, impact on intracellular components, and the destruction of genetic material. Aside from that, plasma-mediated treatments are beneficial enzymatic inactivation and assist with dehydration, resulting in a shelf-life extension. Food processors employ this technology for surface decontamination and impediment for biofilm development. Cold plasma induces bioactive compounds degradation by the combined effects of numerous plasma-reactive species and thermal-induced oxidative cleavage pathways. Therefore, Issues related to this technology include adverse effects on food components, especially lipids and vitamins, that still require more investigations to improve the practical applicability of this technique.