Reducing bacterial count of immobilized enzymes during production of e.g. lactose free milk, comprises separating bacteria loaded immobilizate from product cycle, inactivating bacteria and entrapping sterilized immobilizate in product cycle

Reducing the number of bacteria of immobilized enzymes used in the production of e.g. lactose free milk, comprises (a) separating an immobilizate full of bacterial load with a residual product, from a product cycle; (b) replacing the residual product from the immobilizate with water or gas; (c) inactivating the bacteria present on the immobilizate with ethanol-water mixture; (d) completely replacing the ethanol-water mixture from the sterilized immobilizate with water, gas or product; (e) entrapping sterilized immobilizate in the product cycle of the enzymatic lactose hydrolysis. Reducing the number of bacteria of immobilized enzymes used in the production of lactose poor- or lactose free milk and related substances, comprises carrying out an enzymatic lactose hydrolysis, in which the enzyme required for the hydrolysis is bound to an insoluble support material to form an immobilizate, where the enzyme and the support material is preferably in the form of beads or membranes or coarse pore systems, and the immobilizate is contacted with the substrate to be hydrolyzed based on the charge. After the reaction, the immobilized enzyme is separated from the product and can be utilized for further batches of substrates or is used over a longer duration in a reactor (feed and bleed). The method comprises the following steps: (a) separating the immobilizate full of bacterial load with a residual product for sterilization, from the product cycle; (b) replacing the residual product from the separated immobilizate with water or gas; (c) inactivating the bacteria present on the immobilizate with ethanol-water mixture; (d) completely replacing the ethanol-water mixture from the sterilized immobilizate with water, gas or product; (e) entrapping sterilized immobilizate in the product cycle of the enzymatic lactose hydrolysis. Die Erfindung betrifft ein Verfahren zur Reduzierung der Keimzahl der bei der Herstellung von lactosearmer oder lactosefreier Milch und verwandten Substanzen eingesetzten immobilisierten Enzyme, bei dem eine enzymatische Lactosehydrolyse durchgeführt wird, bei dem das zur Hydrolyse benötigte Enzym an ein unlösliches Trägermaterial gebunden ist und ein Immobilisat bildet, wobei die Bindung insbesondere auf Kügelchen oder Membranen oder innerhalb von porösen Systemen vorliegt, bei dem das Immobilisat einer Charge des zu hydrolysierenden Substrats beigemischt, nach erfolgter Reaktion auf einfache Weise aus dem Produkt (Spaltungsprodukte) abgetrennt und ei