Use of Rhizopus delemar lipase as compared with other lipases for determination of sn‐2 fatty acids in triacylglycerol

The FA composition in the sn‐2 position of TAG is routinely determined after porcine pancreatic lipase hydrolysis. However, the content of saturated FA increased when a pancreatic lipase preparation with higher specific activity was used. Lipase from Rhizopus delemar was selected as a potential replacement lipase for the following reasons: (i) The FA specificity is nearly equivalent in hydrolysis activity toward FA such as lauric, myristic, palmitic, palmitoleic, stearic, oleic, linoleic, and α‐linolenic acids; and (ii) lipase from R. delemar hydrolyzes fatty acyl residues at the sn‐1,3 positions of TAG. Acyl migration products were present at less than 0.8% in lipase hydrolysates containing 6–14% of sn‐2 MAG. A reproducibility CV of less than 5% was obtained in a collaborative study in which the compositions of the main FA at the sn‐2 position in olive oil were determined using lipase from R. delemar.