Analysis of positional distribution of fatty acids in palm oil by¹³C NMR spectroscopy

Abstract

Abstract The 13 C NMR spectrum of the carbonyl carbons of the acyl groups of triacylglycerols of palm oil has been shown to give the composition of saturated, oleic and linoleic acyl groups at the 1,3‐positions and at the 2‐position of the glycerol moiety. Except for the lack of differentiation of the saturated fatty acids, the 13 C NMR technique provides the same information as the tedious enzymatic hydrolysis cum fatty acid analysis. The carbonyl carbon of the linolenic acyl group (18∶3,[ cis, cis, cis ]‐9, 12, 15) has a chemical shift which is only 0.005 ppm to low frequency of that of the linoleic acyl group (18∶2,[ cis, cis ]‐9, 12), so that the two resonances may not be distinguishable (or resolved) even at a high magnetic field.