A simple method for the analysis of trans fatty acid with GC–MS and AT™-Silar-90 capillary column

The study was aimed to evaluate a simplified gas chromatography method based on the AOAC method 996.06 to analyze the trans fat content in food samples. The gas chromatograph was equipped with mass spectrometer and Alltech AT™-Silar-90 capillary column. Ten kinds of the trans fatty acid standard were separated completely from the cis standard and the chemical composition of the peaks was verified by using the mass spectrum. Under the optimized conditions, the recovery rate for triheptadecanoin was 99.0%, the correlation coefficients of trans fatty acid calibration curve was 0.9998 or higher. It demonstrated that the methylation and hexane extraction procedures used in this method was effective and the result was consistent. The major fatty acids found in the shortening sample were 16:0, 18:0, trans-18:1, cis-18:1, cis-18:2, and cis-18:3. The total trans fat content in the sample was 283.6 ± 18.2 mg/g. The current method was more convenient. It is adequate for the routine analysis of trans fat content in food products with low free fatty acid content.