Liquid aerating apparatus

Apparatus for carbonating liquids, comprising a carbonating chamber (1), first valve means (10,14) for controlling admission of liquid to and discharge of carbonated liquid from the chamber, a gas jet nozzle (18) mounted in the chamber for injecting carbon dioxide gas into liquid contained in the chamber, means for connecting the jet nozzle to a source of pressurised gas including second valve means (21) for controlling the supply of gas, pressure releasing means communicating with an upper part of the chamber and including third valve means (25), characterised in that said first, second and third valve means are electrically actuable and controlled by electronic control means (43) so programmed that in response to a start signal supplied to the control means, the first valve means is actuated for the admission of liquid to the chamber to substantially fill the chamber, after closure of said first valve means the said second valve means is actuated one or more times for periods of set duration for gas to be supplied to the jet nozzle and injected into the liquid, after termination of the gas supply and a short delay the said third valve means is opened to release the pressure in the chamber, and following a further short delay after opening the third valve means the first valve means may be actuated for carbonated liquid to be discharged from the chamber.