The present invention relates to a conduit for conducting gasified liquid, which has a flow restrictor arranged in in-line relation therewith. The restrictor itself comprises an at least one aperture (although two or more can be used in series), with each such being adapted to pass the gasified liquid flowing through the conduit and across a pressure drop from a higher-pressure upstream side of the aperture to a lower-pressure downstream side of the aperture. The aperture is operable to moderate the rate of change in pressure over a transitional pressure drop to mitigate the formation of localized pressures below a critical pressure at which off-gassing from the carbonated liquid results in substantial foam formation. The conduit may take the form of a dispensing tube for use in dispensing an alcoholic beverage from a keg, the tube having a flexible wall deformable under the influence of a restricting actuator to control the partial collapse of the wall and thereby form the restrictor. The tube or flow diameter downstream of the restrictor only gradually or slowly increases.