A traditional cask has a bung hole located along the circumference at the cask’s fattest point. Through the bung hole, fresh beer is racked into the cask, then the bung hole is sealed with a shive, a stopper made of wood or plastic. One of the two flat ends (heads) of the cask also features an opening that is sealed with a smaller stopper known as a keystone. The shive and keystone are placed in the cask before the cask is delivered to its destination.
Once at the destination, the cask is stillaged (stored horizontally in a slightly inclined position) in the cellar and allowed to sit undisturbed for a few days so that suspended yeast and finings can drop to the bottom of the barrel. A day or so before the beer is to be tapped, a wooden spile is driven through the bung to allow excess carbon dioxide to vent. Paul Odell explains when you use a hardwood spile and when you use a soft spile, typically made of porous wood or cork.
In Craft Beer & Brewing Magazine’s online course, How to Brew & Serve Great Cask Beers, BJCP-certified judge Paul Odell walks you through everything you need to know to brew, then serve (both traditionally and through homebrew kegs) great cask beers. Sign up today!