A method for purifying biodiesel, biodiesel precursors, or the mixtures thereof, which contain at least one glycoside wherein biodiesel or a biodiesel precursor or a mixture thereof is incubated with at least one enzyme, in order to convert or cleave said at least one glycoside. The resulting material is useful in many industrial applications, including padding, gaskets, and insulation. The first conductive contact, secured in said dielectric housing on a side wall of the receiving cavity, comprises a contacting section facing said receiving cavity. Its novelty consist of the following combination of desirable features:1.