At the termination of thc beer is drawn off fermentation passed to the stills. Aeration is minimized to eliminate, as far as possib aldehyde formation A number of types of still are used the vast majority of which are continuous in operation. Distillation columns are widely used, usually in combination with doubler column consists of a vertical shell containing a The distillation stripping, entrain series of sieve plates arranged in three sections: ment removal and rectifying. Alcohol and congeners are removed from the beer in the lowest stripping section, the vapour passing to the entrainment removal section where particulate matter is removed. Refinement takes place in the rectifying section. A copper mesh'demister' is sometimes fitted above the rectifying section to remove volatile sulphur compounds from the vapour Some of the vapour is condensed in the first dephlegmator con denser, the remainder passing to the second"vent' condenser, Most of the distillate from the dephlegmator condenser is collected for transfer to the doubler, while the remainder, together with dis tillate from the vent condenser is recycled to the rectifying section of the still.