The effects of temperature, speed of agitation, enzyme concentration, etc., on butyl laurate synthesis using Mucor miehei lipase (LipozymeTM) have been studied. Although the soluble enzyme was quite thermostable in aqueous solution, it deactivated rapidly at and above 40 degrees C in the presence of butanol. This enzyme immobilized on an anion-exchange resin (LipozymeTM)) st-cowed enhanced stability Ias compared to the soluble form) to denaturation by butanol under the same conditions. The denaturation of M. miehei lipase was found to be a function of the butanol concentration in the aqueous phase, and rapid denaturation takes place at the concentration corresponding to its saturation at that temperature.