Mixing chamber for beverage machine

A beverage making machine, comprising:

• a precursor liquid supply to provide precursor liquid used to form a beverage;
• a cartridge holder arranged to receive and hold a cartridge containing a beverage medium used to form a beverage with the precursor liquid;
• and
• a dispensing station including a mixing chamber having a precursor liquid inlet fluidically coupled to the precursor liquid supply, a beverage medium chamber fluidically coupled to the cartridge to receive beverage medium into the beverage medium chamber, and a dispense outlet from which beverage medium and precursor liquid are dispensed, the beverage medium chamber including a chamber inlet fluidically coupled to the precursor liquid inlet and a chamber outlet downstream of the chamber inlet and fluidically coupled to the dispense outlet,
• wherein the mixing chamber is arranged such that, with precursor liquid flowing from the precursor liquid inlet to the dispense outlet, pressurized beverage medium in the beverage medium chamber flows through the chamber outlet to the dispense outlet and flow of precursor liquid into the beverage medium chamber via the chamber inlet is prevented, and with precursor liquid flowing from the precursor liquid inlet to the dispense outlet, precursor liquid flows into the beverage medium chamber via the chamber inlet in the absence of pressurized beverage medium in the beverage medium chamber.