Plasma Degradation of Pesticides on the Surface of Corn and Evaluation of Its Quality Changes

Abstract

Plasma is a surface decontamination tool that is widely used in the food fields for pesticide degradation. In this study the effect of plasma on pesticide elimination from the surface of corn and the corn quality changes were tested as functions of power, air flow rate, treatment time, and frequency. Results indicated that plasma treatment for 60 s at 1000 mL·min−1 air flow rate, power of 20 W, and frequency of 1200 Hz, achieved the largest degradation efficiency up to 86.2% for chlorpyrifos and 66.6% for carbaryl, both of which were below the maximum residues limit of grains. Most importantly, after plasma treatment, there was a remarkable decrease (p < 0.05) in moisture content and starch content for treated corn compared with control. The acid value for treated corn showed a prominent increase (p < 0.05), but within the acceptable range of the standard. The vitamin B2 content of treated corn did not show a significant difference (p > 0.05). All results of this study demonstrated that plasma treatment is a promising technology with the ability to remove pesticide residues on corn while maintaining its quality within acceptable limits.