Shut-off valve especially for pressurized carbonated liquids in automatic beverage dispensers or the like, with an expansion device connected thereto in the form of a hollow-cone-like diffusor, in which an expansion cone is arranged which can be adjusted in the axial direction and the taper of which corresponds at least approximately to the taper of the diffusor, characterized by the feature that the expansion device is arranged in the output of the valve and the expansion cone is provided with several holes which start from its conical surface and open into a central hole which starts from its base. .