Influence of low‐pressure nonthermal dielectric barrier discharge plasma on chlorpyrifos reduction in tomatoes

Abstract

AbstractThis study aimed to investigate the influence of nonthermal dielectric barrier discharge (DBD) plasma on chlorpyrifos reduction in tomatoes. As plasma contains highly reactive species and free radicals, it is expected to cause oxidative degradation of the target pesticide chlorpyrifos into its metabolites, thereby reducing the pesticide concentration. Tomatoes applied with three initial pesticide concentrations ranging from 0.6 to 0.8 ppm were subjected to DBD plasma of 2–5 W for the exposure of 4–6 min. The plasma‐treated and control samples were examined for the concentration of pesticide and the physicochemical attributes. The maximum reduction of 89.18% in the pesticide concentration was observed with 5 W at 6 min, which might be due to the intensified reactions of oxidative plasma species. This was further confirmed by GC–MS analysis, and the predominant metabolite of chlorpyrifos degradation, 3,5,6‐trichloro pyridinol (TCP) was identified in the treated sample. The physicochemical attributes except TSS and pH were also significantly (p < .05) influenced by the plasma treatments. Tomato color index (TI) was enhanced while firmness, bio yield point, carotenoids, and total phenolic contents were decreased considerably after plasma treatment. Thus, the cold plasma would be a promising nonthermal technique to degrade and reduce the organophosphate pesticide chlorpyrifos in tomatoes.Practical applicationsThe present study investigates the potential of cold plasma technique to reduce the pesticide contaminant in the perishable commodity, which would result in a safer as well as intact freshness product. The discovered process conditions, that is, the plasma power of 5 W and the treatment time of 6 min giving maximum pesticide reduction would be efficient as well as economical to consider this method of decontamination as a feasible pretreatment. This would further facilitate its application in processing and distribution lines even on a large scale level to promise the consumers a benign product.