Use of lipolysis in the isolation of sterol esters

The isolation of sterol esters from edible oils is hindered by the presence of relatively large amounts of triacylglycerols that are similar in polarity to the sterol esters. This paper describes the use of lipolysis with porcine pancreatic lipase to selectively hydrolyse the triacylglycerols. The sterol esters can then be readily separated from the resulting free fatty acids, monoacylglycerols and any remaining diacylglycerols by flash chromatography. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) can then be used to analyse and partially identify the intact sterol esters.