Lipase‐catalyzed synthesis of waxes from milk fat and oleyl alcohol

Abstract

AbstractA screening of five lipases was carried out for the synthesis of wax esters from stoichiometric amounts of oleyl alcohol and milk fat in which long‐chain fatty acid content (myristic acid, palmitic acid, stearic acid, and oleic acid) represents 70% of the total fatty acid fraction. The lipases from Alcaligenes sp. and Chromobacterium viscosum both allowed for the best ester synthesis (around 60%) within 2 and 48 h, respectively. Enzeco® Lipase Concentrate gave 30% ester yield within only 2 h. During the time period of 166 h, less than 20% ester synthesis was obtained with Lipozyme™ 10,000L whereas Enzeco® Lipase XX did not catalyze the reaction. Owing to commercial availability, the food‐grade Enzeco® Lipase Concentrate preparation was selected for further experiments with a view to improve wax synthesis. Wax yields were compared for three substrate molar ratios, i.e., 0.5:1, 1:1, and 1.5:1 (alcohol/fatty acid). For 0.5:1 and 1.5:1 substrate molar ratios, the addition of water increased ester yields while the effect of silica gel addition was shown to be minor. The best improvement was obtained at a substrate molar ratio of 1.5:1 with addition of water, leading to 59% wax ester synthesis.