A screw pump for transporting a viscous product is described comprising a cylindrical housing connected to a removable bottom piece in one end and a removable cap in the opposite end, a rotor having one or more screw blades connected to a driving motor, an inlet and an outlet wherein the cylindrical housing is provided with a jacket for supply or removal of heat, and the rotor is provided with one or more internal channels connected to an inlet and an outlet for supply or removal of heat. Such a screw pump is suitable for pumping emulsion susceptible to mechanical or temperature damage. Food emulsions manufactured with reduced or without addition of emulsifiers may be transported using such a pump without mechanical damage to the emulsion.