Closed flow-through apparatus and method for gassifying a dairy-type confection mix by applying a pressure head of nitrous oxide to an enclosed receptacle and projecting the mix into the receptacle and atomizing it therein. Atomization is accomplished by projecting a stream of said mix against a surface in said receptacle or toward a rapidly driven impeller. A metered quantity of an edible refrigerant, such as Freon 115, is also distributed into the mix. After gassification, the saturated mix is vented under the pressure of the pressure head into a freezing chamber which is provided with a valved outlet and a motor driven dasher. A control circuit provides an automatic mode as well as a wash cycle and a dasher drive mode.