Residue change of six pesticides in Chinese liquor produced from sorghum

Abstract

Residue change of six pesticides (triadimefon, lambda-cyhalothrin, beta-cypermethrin, esfenvalerate, pyraclostrobin, and difenoconazole) in Chinese liquor produced from field incurred sorghum was studied. The Chinese liquor was produced through soaking, steaming, fermentation, and distillation process. Residue magnitudes of the six pesticides were determined by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). The results showed soaking process did not significantly reduce the pesticide residues, while the steaming process involving continuous heating could obviously reduce the pesticide residues by 54–72%. Moreover, the fermentation process could remove pesticide residues by 37–65% due to biological degradation. Furthermore, the distillation process could completely remove the residue of lambda-cyhalothrin, beta-cypermethrin, esfenvalerate, pyraclostrobin, and difenoconazole, and remarkably reduce the residue of triadimefon with the processing factor between 0.002 and 0.004. This study demonstrated that the whole process could obviously reduce the residue of contaminated pesticides in Chinese liquor, especially the distillation process.