A necessary part of the production of fresh concrete is to cool the cement or other mixing material mixed with the fresh concrete. According to a known method, said cooling is accomplished, for example, by feeding liquid nitrogen through a feed line to the pneumatic cement feed. The liquid nitrogen evaporates immediately upon contact with the cement. The associated increase in pressure leads to a short-term break in the conveyance of cement. As a result, periodic blow-off of dust occurs through the exhaust unit of the silo, which leads to placing a burden on workers and the environment. According to the invention, it is suggested to arrange a second feed line, parallel to the existing feed line between the supply silo and scale or mixing unit, wherein at least part of the flow of each mixing material is diverted and fed through a cooling unit. In the cooling unit, the mixing material contacts a cooling material which is removed from the cooling unit at the end of the cooling process. For the cooling process, a cryogenic cooling material, for example nitrogen or carbon dioxide, is preferably used. The cooling unit is preferably a fluidized screw cooler or a fluidized bed reactor. The invention allows an exact dosing and temperature target for the cooled mixing material.