An experimental study has been carried out on an integrated reaction system consisting of a stirred tank reactor, a de-emulsifier and an ultrafiltration (UF) unit for simultaneous reaction and product separation during the enzymatic hydrolysis of sun flower oil. The study focuses primarily on how UF performance and enzymatic activity are affected by different components in the reaction products and by the operating parameters of the integrated system. An evaluation of the system productivity and synergistic relationships between the kinetics of the hydrolytic reaction, de-emulsification, and product separation is presented. The reaction system comprised a heterogeneous oil/water system with the free enzyme functioning at the Liquid-liquid interface. In contrast to theoretical expectations, no significant gain in productivity and yield was observed in the operation of reaction and separation simultaneously. The continuous removal of the glycerol produced, surprisingly, resulted in only marginal improvements in overall reaction yield. This may be explained by the complex mass transfer processes occurring at the membrane/liquid interface and due to unsuccessful separation of the produced free fatty acids from both the de-emulsified aqueous and oil phases. The reactor operating parameters were also recorded including oil/water molar ratio and impeller stirring rate and their effect upon the UF flux performance and the stability of the lipase activity determined.