A milk-frothing device may be provided that comprises a mixing chamber which is constructed such that, when the milk flows through the mixing chamber, shear forces act on the milk and lead to mechanical lysis of the proteins contained in the milk and hence effect improved frothing-up of the milk. A drinks preparer may be provided that includes this milk-frothing device. A method may be provided for frothing-up of milk using this milk-frothing device.