A gas chromatographic study of the conjugated linoleic acid and other fatty acid contents of raw milk samples from Galicia (NW Spain)

ISO/IDF procedures were adjusted to extract the fat from milk samples and derivatise it into fatty acid methyl esters for their analysis by two gas chromatography methods: one for the determination of cis‐9,trans‐11‐octadecadienoic acid; another, to study the fatty acid (FA) profile of samples. Both methods exhibited good precision, produced reliable results and were applied to the analysis of tenths of raw milk samples. The data were statistically explored to check whether different farms produced different FA profiles, and there seemed to be differences (not confirmed) among some of the farms.