A method for treating liquid food products after direct heating comprises a first cooling of the liquid food product occurring on a floor of the infuser vessel up to an outlet opening. A second cooling of the liquid food product occurs in a tubular section connecting directly to the outlet opening. A third cooling of the liquid food product occurs in a housing cover of a pump housing of a centrifugal pump. At least one flushing operation of the pump housing and of an impeller via a rear impeller gap is performed, wherein the at least flushing operation occurs via a front impeller gap located between the housing cover and the impeller. Volume flows of the at least one flushing operation are greater than equalization flows within the pump housing.