Disclosed is a process for the preparation of an interfacial enzyme immobilized on an insoluble support, by providing a bi-phase system comprised of an aqueous buffer solution and at least one first organic solvent; mixing said interfacial enzyme with the bi-phase system provided; adding the support to the obtained mixture and mixing; and isolating from the mixture obtained in the last step the interfacial enzyme immobilized on said support. The produced enzyme is locked in its catalytically active confirmation, and thus exhibits improved activity and stability. Also disclosed are uses of the produced enzymes, particularly in the preparation of biodiesel.