Carbonation

Carbonation is created by dissolved carbon dioxide in the beer. This can be achieved in two ways: by adding extra sugar and yeast to the bottle, keg, or cask, and allowing the yeast to create carbon dioxide through fermentation, or by forcing pressurized carbon dioxide into a container (usually a keg) and allowing it to dissolve into the beer.

Bottle conditioning

Cask conditioning

Cask conditioning is a process similar to bottle conditioning, but instead of a bottle the priming sugar and yeast are added to a cask. While the process is the same, the larger volume lends a different character to finished bottle- and cask-conditioned beer.

Keg conditioning

The term keg conditioning is sometimes used for cask conditioning beer in a standard homebrewer's Cornelius keg. However, since a cask can be made of metal, there is no functional difference between cask and keg conditioning, except that a few additional steps must be taken to adapt the keg to keg conditioning:

• Shorten the dip tube. Cornelius kegs generally have a dip tube that reaches to the very bottom of the keg. Removing a small amount of this dip tube will prevent yeast sediment generated during conditioning from being drawn up first when the keg is tapped.
• Start conditioning at low pressure. Some home brewers prefer to leave a small amount of pressure on the beer while the conditioning process is beginning to ensure a seal until enough pressure builds up from the fermentation.

The beer can then be served from a hand pump or under low carbon dioxide pressure.

Force carbonation