Apparatus for changing the temperature of an infusible liquid from a first temperature to a second predetermined temperature. The apparatus includes a receiver assembly for changing the temperature of the liquid. The apparatus also includes a cartridge to be received in the assembly and which defines an enclosed passageway for movement of the fluid. The cartridge has a first end, a second end, a liquid inlet disposed adjacent the first end, a liquid output disposed adjacent the second end, and a first wall extending between the ends and made of a material having good heat transfer properties. The assembly includes a thermoelectric heat pump, and a slot is provided for releasably receiving the cartridge so that the heat pump engages the wall of the cartridge. The assembly also includes a temperature sensor engaging the wall adjacent the ouptut and an electric circuit which is responsive to the temperature sensor for controlling operation of the heat pump so that the liquid exiting the cartridge is at the predetermined temperature.