A cocoa butter improver (CBI) is a 
specific heat-resistant cocoa butter equivalent (CBE), wherein 
glycerol-1,3-distearate-2-oleate (SOS) having higher 
melting point constitutes the main component in the 
triglyceride composition of the CBI. In the invention, the 
biosynthesis of the cocoa butter improver comprises the following steps: firstly, carrying out 
transesterification reaction preferably among SOS with a high content, and 
glycerol-1,2-distearate-3-oleate (SSO) and tri-
stearin (
SSS) with a low content in the presence of 1,3-specific lipases as a catalyst under the optimized conditions of the 
transesterification reaction; carrying out molecular 
distillation on the product obtained from the optimized 
transesterification reaction to remove 
fatty acid from the product, wherein the optimization is carried out by targeting on the heavy-phase yield and 
acid value; and carrying out wet 
fractionation on the deacidified product by using 
acetone, n-
hexane and other solvents, wherein the conditions of 
fractionation are optimized by targeting on the yield of SOS-rich 
stearin. A large amount of 
stearic acid (or low-grade 
alcohol ester thereof) obtained through the removal of 
fatty acid in the molecular 
distillation and the palmitic components of SOO and OOO as the main 
triglyceride composition obtained through the follow-up 
fractionation are recyclable as the raw materials for the transesterification, thus improving the 
utilization rate of raw materials. The CBI prepared through the 
biosynthesis of the invention is applicable as the 
raw material for the production of heat-resistant chocolate in the 
food industry.