title: Enzymatically catalyzed synthesis of low-calorie structured lipid in a solvent-free system: optimization by response surface methodology.
abstract: A kind of low-calorie structured lipid (LCSL) was obtained by interesterification of tributyrin (TB) and methyl stearate (St-ME), catalyzed by a commercially immobilized 1,3-specific lipase, Lipozyme RM IM from  Rhizomucor miehei . The condition optimization of the process was conducted by using response surface methodology (RSM). The optimal conditions for highest conversion of St-ME and lowest content LLL-TAG (SSS and SSP; S, stearic acid; P, palmitic acid) were determined to be a reaction time 6.52 h, a substrate molar ratio (St-ME:TB) of 1.77:1, and an enzyme amount of 10.34% at a reaction temperature of 65 °C; under these conditions, the actually measured conversion of St-ME and content of LLL-TAG were 78.47 and 4.89% respectively, in good agreement with predicted values. The target product under optimal conditions after short-range molecular distillation showed solid fat content (SFC) values similar to those of cocoa butter substitutes (CBS), cocoa butter equivalent (CBE), and cocoa butters (CB), indicating its application for inclusion with other fats as cocoa butter substitutes.
authors.affiliation: School of Food Science and Technology, Jiangnan University, State Key Laboratory of Food Science and Safety, 1800 Lihu Road, WuXi 214122, Jiangsu, People's Republic of China.
authors.forename: Lu
authors.initials: L
authors.lastname: Han
authors.forename: Zijian
authors.initials: Z
authors.lastname: Xu
authors.forename: Jianhua
authors.initials: J
authors.lastname: Huang
authors.forename: Zong
authors.initials: Z
authors.lastname: Meng
authors.forename: Yuanfa
authors.initials: Y
authors.lastname: Liu
authors.forename: Xingguo
authors.initials: X
authors.lastname: Wang
mesh_terms: D018752:Diet, Fat-Restricted; D004041:Dietary Fats / Q000032:analysis; D002149:Energy Intake; D004951:Esterification; D005227:Fatty Acids / Q000032:analysis; D008049:Lipase / Q000378:metabolism; D014280:Triglycerides / Q000096:biosynthesis* / Q000737:chemistry*
chemical_list: D004041:Dietary Fats; D005227:Fatty Acids; D014280:Triglycerides; C052387:cocoa butter; C117372:salatrim; C093666:Lipozyme; D008049:Lipase; C005830:tributyrin