TY - JOUR TI - Degradation kinetics of seven organophosphorus pesticides in milk during yoghurt processing AU - Bo Li-Yingx AU - Zhang Ying-Hua AU - Zhao Xin-Huai JN - Journal of the Serbian Chemical Society PY - 2011 VL - 76 IS - 3 SP - 353 EP - 362 PT- Article AB- Bovine milk spiked with seven organophosphorus pesticides, i.e., dimethoate, fenthion, malathion, methyl parathion, monocrotophos, phorate and trichlorphon, was fermented at 42°C with commercial directed vat set (DVS) starters to investigate the degradation kinetics of the pesticides during yoghurt processing. The spiked pesticides were extracted from the prepared samples with an organic solvent and analyzed by gas chromatography after purification. Based on published results that the degradation kinetics of pesticides is first order, the rate constant of degradation and the half live period of the pesticides were calculated. The results indicated that degradation of the pesticides in milk during yoghurt processing were enhanced by one or both starters, except for malathion, and the two commercial DVS starters had different influences on the degradation kinetics of the pesticides.