气相色谱-质谱法测定脂肪酸组成鉴别地沟油的方法研究

Identification of Hogwash Oil by Analysis of Fatty Acids with Gas Chromatography-Mass Spectrometry

建立了分析油脂样品中37种脂肪酸含量的气相色谱-质谱检测方法,通过对100多种植物油和20多种地沟油的37种脂肪酸含量的分析,总结出了根据37种脂肪酸含量鉴别地沟油的判定依据。低碳数饱和脂肪酸是地沟油与植物油差异较大的组分,但是应用气相色谱方法测定时无法对其进行准确的定性定量,从而无法根据低碳数饱和脂肪酸的组成进行是否地沟油判定。应用气相色谱-质谱方法,提高了方法的灵敏度,完善了根据脂肪酸组成判定地沟油的依据。应用该判定依据,对卫生部两次盲样进行判定,阳性准确率分别为100%和95%,阴性准确率分别为100%和90%,表明该判定依据是一种有效且准确率较高的鉴别地沟油的方法。

A gas chromatography-mass spectrometry method was established to analyze the contents of 37 fatty acids in more than 100 vegetable oils and 20 hogwash oils.The criterion of hogwash oil was made in accordance with the content of 37 fatty acids.Low carbon number of saturated fatty acids is of significant difference between hogwash oil and vegetable oils.However,when analyzing by gas chromatography with FID detector,the sensitivity is too lower to be differentiated.By using gas chromatography-mass spectrometry,the sensitivity and the criterion for hogwash oil were improved.According to the new criterion for hogwash oil,the both two blind tests were of more than 90% accuracy.And it is showed that it is an effective and high accurate method.