Abstract: The present invention relates to a continuous process for the enzymatic preparation of isomaltulose. A periplasmatic sucrose-mutase is produced by fermentation of microorganisms which form sucrose-mutase. The cell-free crude enzyme extract is prepared by digestion of the cells and by cross-flow microfiltration. In a single-stage, simultaneous purification and immobilization of the sucrose-mutase from the cell-free crude extract conditioned by diafiltration is obtained by selective bonding to an anionizable carrier matrix. Direct conversion of sucrose into isomaltulose is produced by the sucrose-mutase bonded to the anionizable carrier matrix, preferably in cartridge or cartouche form.

Abstract: When immobilizing cells and/or enzymes by contact with tannin, epihalohydrin/polyamine copolymer and glutaraldehyde, immobilizing is carried out in the presence of a primary amine. The primary amine is preferably sulfuric acid mono-(2-aminoethyl)-ester, 2-aminoethanol, glycine or tris-(hydroxymethyl)-amino methane. The resulting immobilized cells and/or enzymes retain a higher proportion of their original activity.