The invention relates to a method and to a device for controlling foaming in a degassing device (10； 10.1, 10.2) for liquids (P), in particular liquid foods such as milk, semi-skimmed milk, skimmed milk, or fruit juices, and to a heat-exchanger system (20) for such a device. The aim of the invention is for the method, the device for performing the method, and the heat-exchanger system to effectively control and limit foaming and to prevent the growth of the foam beyond a tolerable amount while ensuring the sanitary and hygienic process-control requirements in the field of the treatment and processing of liquid foods. This aim is achieved in respect of process engineering, inter alia in that the growing foam (S), beginning at a first heating distance (h1) from the free surface (N) releasing the foam (S) and beginning at a second heating distance (h2) from the liquid film (F) releasing the foam (S), first experiences heating from the liquid temperature (T3) to a heating temperature (T1) in the heat-exchanger system (20), which consists of a heating heat exchanger (20.1) and a cooling heat exchanger (20.2), and that the further growing heated foam (S), beginning at a first cooling distance (k1) from the first heating distance (h1) and beginning at a second cooling distance (k2) from the second heating distance (h2), then experiences cooling to a cooling temperature (T2) in the heat-exchanger system (20).
