Effect of cold plasma treatment on microbial load reduction and physicochemical properties of turmeric

Cold plasma is a dry, non-thermal technology with no chemicals capable of working continuously at atmospheric pressur. In the present study, plasma discharge of atmospheric pressure dielectric barrier with gases (air, nitrogen, and argon) was applied to the plasma for (0,5,15,25) min at the surface of curcuma longa samples to reduce total microbial, coliform, yeast and mold, Clostridium perfringens was performed. Results of microbial tests showed that irradiation of plasma with nitrogen gas for 15 minutes reduced curcuma longa microbial load with minimal effect on physicochemical properties.Control samples lacked coliform and Clostridium perfringens. The results of physicochemical properties of the samples (color and antioxidant activity) showed that the effect of gas type on any of the curcuma longa color indices was not significant, while with increasing plasma duration the mean of all three color indices decreased, which decreased in There were significant differences between 15 and 25 minutes.(p<0.05). nvestigation of the effect of gas type and duration of plasma application on the inhibitory index of curcuma longa samples showed that the type of gas used had no effect on this index(p>0.05), while the effect of time was significant for this index and their antioxidant properties compared to the control sample Decreased(p<0.05). The results of sensory characteristics (color, odor, appearance and taste) of the samples showed that the type of gas used did not differ significantly on the sensory parameters of the samples, while with increasing plasma duration the mean values ( Except for the taste index of the samples which decreased significantly between 15 and 25 minutes(p<0.05). In general, cold plasma is a novel method of food processing that, given its non-thermal nature, can be a good alternative to other methods used for food sterilization and pasteurization.