In situ transesterification of fatty acids from Iberian pig subcutaneous adipose tissue

The purpose of this study was to optimize a rapid method for fatty acid analysis in Iberian pig subcutaneous adipose tissue. An in situ transesterification method was used to avoid the lengthy lipid extraction step. Samples were in situ transesterified with 5% HCl/methanol at 70°C, and toluene was used to help dissolve lipids. The method had advantages over other in situ methods since only 45 min were required to completely transesterify the fatty acids, and 10 min to obtain the fatty acid profile. A sample size of 25 mg of adipose tissue was suitable. The in situ transesterification gave higher fatty acid concentrations than conventional lipid extraction and transesterification, the differences being significant for all the fatty acids. Relative fatty acid contents were similar to those found by the conventional method.