Due to their high synthetic potential in regard to chemo-, regio- and stereoselectivity, enzymes have started to play an important role in modern chemistry. New interesting synthetical pathways were developed, since it has been shown that lipases are catalytically active even in anhydrous organic solvents. Although the number of publications dealing with enzymatic synthesis in unconventional solvent systems is still increasing, few works have been published with respect to chemical engineering aspects. In this paper, the optimization of a stereoselective esterification using lipases in organic solvents is reported.