An assembly for creating milk froth and/or for heating milk is disclosed. It comprises a foaming device and optionally a milk container and a valve assembly. The foaming device is provided with a steam supply channel, an air supply channel, a milk supply channel and a discharge opening. In order to provide for an easy cleaning of the assembly and its microbicity, at least the components and/or cavities coming into contact with milk are provided with a hydrophobic and oleophobic surface consisting of nano-particles which consist partially of silver or a silver compounds.