Abstract: The apparatus for the treatment of substances, in particular foods, has a condensation device which is constructed within the cooking chamber (2) and comprises an injector nozzle (16) and a condensation chamber (23) which is constructed as a recess (12) in the cooking chamber bottom. The injector nozzle (16) is further situated within the pressure region (13) of a circulation fan (5). The recess (12) which acts as condensation chamber leaves from the pressure region (13) of the circulation fan (4) and extends into the cooking chamber (2).