The Saturated sn‐2‐Triglycerides of Palm‐Kernel Oil

The saturated sn‐2‐triglycerides (the fatty acid esterified at the 2‐position is known) of palm‐kernel oil, representing 78%, was isolated by argentation thin‐layer chromatography. The nine groups of this fraction (triglycerides with the same total acyl carbon atoms) were fractionated by gas‐liquid chromatography and their component fatty acids determined. From the fatty acid composition of each group it was possible to determine mathematically the component triglyceride types of the group (the 3 fatty acids are known, but their positional distribution is not). The proportion of 46 types were calculated in this way. The major fractionate groups (6 out of 9) were hydrolyzed by pancreatic lipase. From the component 2‐mono‐glycerides it was possible to determine the proportion of 44 sn‐2‐triglycerides which account for 75% of the oil triglycerides. Trilaurin (21%) is the major component, followed by sn‐2‐lauro‐1,3‐lauromyristin (12%). These two triglycerides together form one third of the glyceride content of the oil. Sn‐2‐lauro‐1,3‐caprylolaurin (7%), 5 sn‐2‐triglycerides (2 to 5%), 9 (1 to 2%) were also found, and 27 triglycerides present at less than 1%. The calculated 1,3‐random‐2‐random distribution of fatty acids on glycerol molecules exhibited great differences from the experimentally determined distribution. Consequently, calculations of this kind cannot replace a complete analytical analysis of palm‐kernel oil such as the one reported in this work.