Comparison of methods for the quantitative determination of tall oil fatty acids by gas chromatography

A gas‐chromatography procedure, using methyl margarate as an internal standard, has been applied to the quantatitive determination of unsaturated tall oil fatty acids. Such an internal standard is necessary for accurate analyses, especially if components of the unknown are present which are not sufficiently volatile to be measured in the chromatograph. The acids are converted to methyl esters before being chromatographed. The preparation of reliable standards, methods of esterification, accuracy obtained on prepared standards using both thermal conductivity and beta‐ray ionization detectors, and analyses of tall oil samples, are discussed.