Dissipation of Pesticide Residues on Grapes and Strawberries Using Plasma-Activated Water

In this study, we present a novel atmospheric air plasma discharge for the generation of plasma-activated water (PAW), with the aim of reducing pesticide residues on fresh fruit. For this purpose, a large discharge volume pin-to-plate cold plasma reactor was employed. The pesticide-spiked grapes and strawberries were processed with varying PAW concentrations to study their efficacies for pesticide degradation combined with an evaluation of any induced changes in key nutritional and quality attributes. The results suggest that the reduction of chlorpyrifos was 79% on grapes and 69% on strawberries while that of carbaryl was 86% on grapes and 73% on strawberries, respectively. The degradation of pesticides in PAW is due to the generation of metastable reactive species including nitrates, nitrites, and hydrogen peroxide. The high oxidation potential and acidic environment of this PAW are proposed as important actors for pesticide dissipation. In addition to the effective pesticide reductions obtained, there were no significant changes in the key physical attributes (color and firmness) of the treated samples and only slight changes in the ascorbic acid levels observed for both strawberries and grapes. This study points to the effective potential of PAW for chemical decontamination of fruit while maintaining important quality and nutritional parameters