An apparatus for foaming a liquid is disclosed. The apparatus includes a pump for pumping an aerated liquid to an outlet via a conduit (7). The conduit (7) includes at least one flow resistor which encloses a plurality of adjacent elastic resistor elements (20a) which are movable relative to one another and form passages for the liquid to pass. The resistor elements (20a) are supported against a support (27) and are compressed against the support (27) by the pressure forces (26) of the liquid forced through the resistor. The resistor reduces pressure pulses caused by the pump. The apparatus may be used for frothing milk for a beverage.
