二阶导数傅里叶变换红外光谱鉴别植物油和地沟油

利用傅里叶变换红外光谱法测定了食用植物油、地沟油和模拟的复热油的光谱并进行二阶导数处理分析。结果表明:地沟油和模拟的复热油的饱和脂肪酸、反式脂肪酸的含量均明显高于正常食用油的;二阶导数光谱中3 009、1 737、966、723 cm~(-1)4处特征吸收峰的变化可作为判定是否为地沟油的参考。用此方法鉴别油品用量少且无需样品预处理,分析速度快,可为地沟油检测方法的建立提供依据。

Discerning of vegetable oils and swill-cooked dirty oils by second derivative Fourier transform infrared spectroscopy

The second derivative spectra of edible vegetable oils, swill-cooked dirty oils, and simulated reheated edible vegetable oils were analyzed using Fourier transform infrared spectroscopy method. The results showed that the contents of saturated fatty acids and trans fatty acids in swill-cooked dirty oils and simulated reheated edible vegetable oils were significantly higher than those of normal edible oil. The changes of characteristic absorption peaks at 3 009,1 737,966,723 cm^-1 in second derivative spectra could be used to identify swill-cooked dirty oils. The method had the items of less consumption of samples, no pre-treatment and rapid velocity of analysis. The results provided the foundation to establish an identification method of swill-cooked dirty oils.