Abstract: An immobilized sn-1, 3-specific lipase from Rhizomucor miehei was used to catalyze the interesterification of Palm Mid Fraction (PMF), Palm Kernel Stearin (PKS) and Medium Chain Triacylglycerols (MCT) under controlled reaction parameters such as enzyme load, time course and temperature to produce a low calorie Cocoa Butter Substitutes (CBS). Samples were analyzed for physical (slip melting point, solid fat content) and chemical properties (fatty acids and triacylglycerol composition) and compared with cocoa butter. Quantitative analysis of the reaction mixture was conducted by using High Performance Liquid Chromatography (HPLC), which enabled the exact tracing of the triacylglycerol synthesis of rearrangement. In this study, 4 samples based on palm products (PMF, PKS, PMF: PKS, EIE PMF: PKS: MCT) were analysed including cocoa butter. The solid fat content for all samples at all measured temperature showed the sharp melting properties in a range of 15° to 30°C. A-PMF showed higher SMP (34°C) compared to others and the lowest was D-EIE fat (31°C) which means that the structured CBS is softer. The rearrangement of fatty acids between medium chain fatty acids and long chain fatty acids contribute structured triacylglycerols which might affected the calorie value of the CBS.