食用油脂中37种脂肪酸和16种反式脂肪酸的气相色谱分离及测定

Separation and Determination of 37 Fatty Acids and 16 Trans Fatty Acids in Edible Fats and Oils by Gas Chromatography

建立一种多组分分离、测定动植物油脂中37种脂肪酸和16种反式脂肪酸含量的气相色谱法。食品中的油脂经酯交换法甲酯化,在HP-88毛细管柱上得到分离,采用气相色谱FID检测器测定,以面积归一化法定量。结果表明, 37种脂肪酸甲酯和16种反式脂肪酸甲酯在其浓度范围内均呈现良好的线性关系,线性相关系数r≥0.999,检出限为0.000 1%~0.001 3%。采用该方法测定几种典型的标准油品和质控样品,其脂肪酸含量与给定值一致,相对标准偏差为0.82%~5.53%。该方法操作简便、快速准确、重现性好,适用于批量检测。

An attempt was made to establish an optimum separation and determination method for 37 fatty acids and 16 trans fatty acids in edible fats and oils by using gas chromatography （GC）. The fats and oils in foods were methylated to fatty acid methyl esters by the transesterification method, separated on HP-88 capillary column and analyzed by GC with FID detector. Fatty acids were quantitatively measured by the peak area normalization method. The results showed the 37 fatty acid methyl esters and 16 trans fatty acid methyl esters had good linearity in a certain range of concentration, with the linear coefficients （r） being ≥0.999 and the detection limit ranging from 0.000 1% to 0.001 3%. The standard edible vegetable oils and quality control samples were also measured by this method, the fatty acids content was consistent with the assigned value. The relative standard deviations ranged from 0.82% to 5.53%. This separation and determination method was simple, rapid and accurate. It was suitable for inspection in batches.