National Engineering Research Center for Functional Food, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, National Engineering Laboratory for Cereal Fermentation Technology, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, People's Republic of China. [Email]
Structured lipids (SLs) rich in conjugated linoleic acid (CLA) and butyric acid with functions of low calorie and weight loss were synthesized in this study. By comparison of different synthetic routes, transesterification of CLA ethyl ester (CLAee) and tributyrin under vacuum was determined as the best method. The reaction conditions for SL synthesis were screened and the best conditions were as follows: Novozym 435 as the catalyst, enzyme load 6 wt%, temperature 60 °C, substrate molar ratio 2:1 (CLAee/tributyrin), water activity 0.68, reaction time 80 min. Under these conditions, the final product contained 97.5% of SLs, in which the contents of dibutyl-conjugated linoleoyl-glycerol and butyl-diconjugated linoleoyl-glycerol were 78.4% and 19.1%, respectively. The reusability evaluation indicated that the lipase could be reused at least 17 times. The obtained SLs with functions of both fatty acids could replace natural oil in food for inhibition of obesity and thus have great potential for commercial applications.