Lipase-catalyzed modification of butterfat via acidolysis with oleic acid

During the last decade increased interest in reactions catalyzed by lipases from various microbial sources has prompted attempts to rationally design lipases and lipase-catalyzed processes aiming at modification of functional properties of oils and fats. The present communication reports experimental work on the chemical modification of anhydrous butterfat via interesterification reactions with oleic acid catalyzed by a commercial lipase immobilized by plain physical adsorption on a bundle of hydrophobic hollow fibers. The main goal of this research effort was to engineer butterfat so as to increase its level of unsaturated fatty acid residues (viz. oleic acid) and concomitantly decrease its level of medium-to-long chain saturated fatty acid residues (viz. myristic and palmitic acids). All reactions were carried out at 40 degrees C in the absence of any solvent but under controlled water activity, and their extent was monitored via chromatographic assays for free fatty acids. Although a certain degree of net hydrolysis of butterfat was observed, the enzymatic process studied was technically feasible and able to reach the predefined goals.