Detection ofcis-vaccenic acid in palm oil by13C NMR spectroscopy

The NMR signals of the carbonyl and olefinic carbons of the oils of some species of palm show some relatively weak peaks at characteristic positions that have not been identified previously. These peaks are most intense in the oil of the speciesElaeis oleifera. On the basis of the chemical shift data of the carbonyl and olefinic carbons of several synthetic monoenic triacylglycerols and of the packed-column gas chromatogram of the methyl esters of the oil ofE. oleifera, the peaks in question are assigned tocis-vaccenic acid (18∶1,[cis]-11).¹³C NMR spectroscopy is an effective technique for the detection ofcis-vaccenic acid and other monounsaturated fatty acids in vegetable oils or fats.