A process for producing lactose-free dairy products is suggested, comprising the following steps:(a) Hydrolysis of a starting milk while adding lactase(b) Nanofiltration of the hydrolysis product for producing a first permeate P1 and a first retentate R1 (c) Reverse osmosis or nanofiltration of the first permeate P1 for producing a second permeate P2 and a second retentate R2 (d) Mixing the first retentate R1 with such an amount of the second permeate P2 and the retentate R2 that a standardized dairy product is obtained, the content of proteins and minerals of which correspond to the one of the starting milk.
