The invention relates to a milk-frothing apparatus, in particular for a coffee or espresso machine, comprising a froth-generating unit (22) which is in the form of a disposable part, which is easy to replace, and has a mixing chamber (40), an outlet (39), which leads to the outside from the mixing chamber (40), for the generated milk froth, and first means (42) through which the froth-generating unit (22) is supplied with steam and air (53), and also second means (43) through which the froth-generating unit (22) is supplied with milk, wherein the froth-generating unit (22) can be connected to a holding means (30) in a detachable manner. The froth-generating unit (22) can be replaced in a simple and reliable manner while at the same time operating in a flexible manner by the first means comprising a first inlet (42) through which steam and air enter the froth-generating unit (22) together, by a combined steam/air nozzle (33), which projects outward and is connected to a steam generator and an air pump and through which steam and air are routed together, being provided on the holding means (30), and by the first inlet (42) and the steam/air nozzle (33) being designed and matched to one another such that they form a detachable hydraulic plug connection.