Bottle conditioned beer (thing)

When buying a bottled English ale, look for the magic words bottle conditioned on the label. What you are buying is a superior product: real ale in a bottle.

With ordinary bottled beers, the yeast is killed by pasteurisation and filtered out, and carbon dioxide is added. With a bottle conditioned beer, live yeast is left in, and some sugar is added for secondary fermentation in the bottle.

A word or warning: Be careful how you keep a bottle of conditioned beer. Firstly, the beer needs time to mature, and the secondary fermentation process to work. If you serve a bottle conditioned beer too early (too young), it will be flat. Unless you are in a tropical climate, you want to keep a bottle conditioned beer outside the refrigerator (but it's OK to chill it before serving), as the yeast likes 10-20^oC. Too warm, and the beer will condition too rapidly and turn to vinegar.

Secondly, careful how you pour, as the beer contains sediment in the bottom, which you don't want to drink. Though some people deliberately drink the sediment for its laxative properties.

Outside the United Kingdom, bottle conditioned beers may be difficult to obtain. Nevertheless, here are a few brands to look out for. ABV stands for Alcohol by volume.

• Fuller's 1845 (6.3% ABV)
  Originally brewed as a 150 years celebration ale, the brewery found the product so popular, they continued to brew it for the UK supermarket and off licence trade.
• Bishop's Finger, brewed by Shepherd Neame
• Young's special London ale (6.4% ABV)
• Worthington's white shield
  This product is not as good as the others, but is probably more widely available internationally, as it is brewed by one of the brewery giants Interbrew, formerly Bass.