The determination of the position of the double bond in mono‐ethenoid fatty acids

Abstract

Abstract Methods hitherto used for determining the position of the double bond in the fatty acid molecules are somewhat crude and unreliable when applied to fatty acid mixtures. Applying partition chromatography to the analysis of fatty acid oxidation products more reliable results were obtained. Experiments have shown that ozonisation and permanganate oxidation in glacial acetic acid cause only a slight secondary disintegration of the dibasic acids formed, but that permanganate oxidation in acetone is less suitable. The improved method as described does not yield fully quantitative results, but it is sufficiently good to permit valuable conclusions to be drawn. The method is checked by the analysis of pure samples of various fatty esters. “Vaccenic acid” obtained by partial hydrogenation of tang oil has been proved to be a mixture of isomeric oleic acids.