Application of non-thermal plasma for decontamination of thyme and paprika

Abstract

The decontamination importance of spices as a widely used product in the world and the limitations of conventional decontamination methods conduct to find new and safe ways for microbial reduction of spices. Recently, cold plasma technology has been considered as a technique for disinfection in the food industry. In this study, microbial destruction of thyme and paprika through non-thermal plasma was investigated. The implemented method to create atmospheric cold plasma was dielectric barrier discharge (DBD). Plasma was applied to spices for 5 minutes. The results showed that by applying non-thermal plasma to thyme, total bacterial counts were reduced to 1.18 log cycle, but molds and yeasts were not changed. For paprika, considerable effects were not observed. It seems that cold plasma as an inexpensive, water-free and non-thermal method has the potential to reduce the bacterial contamination of thyme but further research is required to improve its effect. It is also possible to use DBD plasma treatment in combination with other technologies.