四种农药在莼菜加工过程中的残留量变化

为了考察敌百虫、毒死蜱、氯氰菊酯和多菌灵4种农药在莼菜加工过程中的加工因子，从而优化莼菜的加工过程，分别模拟莼菜加工的清洗、杀青、护绿和储藏4个步骤，考察4种农药的加工因子，并分析每个步骤的相关因素对加工因子的影响。采用气相色谱-火焰光度检测器（GC-FPD）检测敌百虫和毒死蜱的含量，气相色谱-电子捕获检测器（GC-ECD）检测氯氰菊酯的含量，液相色谱-二极管阵列检测器（LC-DAD）检测多菌灵的含量。结果表明:随着清洗时间的增加，4种农药的加工因子逐渐变小，并在一定时间后趋于稳定；在供试的10 min内，杀青时间越长，4种农药的加工因子越小；护绿和储藏条件的改变对加工因子均无显著影响。综合考虑莼菜品质和农药残留两方面因素，建议莼菜清洗时间为30 min，在不影响莼菜品质的前提下尽量延长杀青时间。

Residue changes of four pesticides in Brasenia schreberi Gmel during processing

The processing factors (PF) of 4 pesticides (trichlorphon, chlorpyrifos, cypermethrin, carbendazim) in Brasenia schreberi Gmel were investigated in order to improve the processing treatment. The washing, blanching, green-protecting, and storage processing were simulated and the effects of each processing on PF of the above 4 pesticides were studied. The residues of trichlorphon and chlorpyrifos were detected with GC-FPD. And the residues of cypermethrin and carbendazim were determined by GC-ECD and LC-DAD, respectively. The results showed that PF of 4 pesticides reduced gradually with the increasing of washing time. However, it reached to a stable state after a certain time. Within the range of 10 minutes, the PF of 4 pesticides kept reducing with the increasing of blanching time. There were no significant effects of green-protecting and storage processing on the PF of 4 pesticides. Given the quality and pesticide residues of B. schreberi, about 30 minutes'' washing time was recommended, and the blanching time should be extended as long as the quality is not influenced.