A pipe-closing apparatus of a machine which is suitable for processing foodstuff mixtures, contains a throttling valve arranged in a pipeline and has a closing element configured with respect to the pipeline with two sealing sections. The apparatus further has an activation apparatus for transferring the closing element into an open or closed position and vice versa. Accordingly, the closing element is formed by a three-dimensional rotationally symmetrical body which has a passage, wherein, in the open position of the closing element, at least the inlet and outlet openings of the passage are aligned with the pipeline, and, in the closed position, the passage is subjected to a pressure for the ingress of compressed air. The pipe-closing apparatus is suitable equally for use in a machine for producing a milk-containing ice cream and for processing and/or preparing, for example, caramels, jams, sweets, crème bavaroise, milk creams and confectioner's creams.
