Lipase-catalyzed glycerolysis extended to the conversion of a variety of edible oils into structural fats

Abstract

Lipase-catalyzed glycerolysis was recently shown to be a viable technique to structure cottonseed and peanut oils into structural fats by converting native triacylglycerols into partial glycerides without changing overall fatty acid composition. Here, this approach was extended to a variety oils of differing fatty acid compositions. Reactions were performed at 65 ​°C for 48 ​h at a triacylglycerol:glycerol molar ratio of 1:1, using the non-regiospecific Candida antarctica lipase B. In all oil systems, a 20 ​°C increase in crystallization onset temperature was observed following glycerolysis. Solid fat content increases resulting from glycerolysis were greatest for oils containing >10% saturated fat along with a high oleic acid content. The solid fat content of tigernut oil at 5 ​°C increased from 8% to 34% following glycerolysis. Tigernut glycerolysis product was used to make margarine with plasticity similar to commercial margarine and butter. This research demonstrates that glycerolysis is a general strategy to convert liquid oils into structural fats used in food applications, and thus replace palm oil and hydrogenated fats.