Be honest. When you think of British beer you picture it warm and flat, served from a hydraulic hand pump. This is the reputation cask ale has suffered through from people outside of the United Kingdom.
First off, let’s get this straight: cask ale is not warm. It is not flat. Sure, it’s not as cold or as carbonated as many of the beers we’re used to drinking in the United States, but that’s not a bad thing.
“Any beer that is truly warm and flat would be undrinkable,” explains Alex Hall, a brewer, cask ale expert and beer entrepreneur. “Cask beer in good condition with a gentle, naturally produced carbonation is many miles away from that description.”
Cask ale, also known as traditional ale or as real ale, is very much a living product. After the ale is brewed it is transferred to metal (less frequently wooden) casks and then pitched with a fresh dose of yeast. This process is known as secondary fermentation and it is what creates the rounded flavors of the ale along with the additional natural carbonation as the yeast chews on the beer’s sugar. The casks are transferred and stored in the pub cellar where it is the job of the cellar man to maintain the proper storage temperature – usually 55 to 57 degrees – and to ensure the beer is aging to the brewer’s specifications. In some cases a cask needs only a few days to reach its desired level. In other cases it can take several weeks or longer to reach perfection. The importance of the cellar man must not be understated; the profession is vital to ensuring that customers get the freshest and best tasting beer possible.
If all is done correctly the end result should be brilliantly clear and look lively in the glass, with natural carbonation lazily making its way to the surface.
“We don’t like warm beer at all,” said Roger Protz, a beer historian and editor of the Good Beer Guide. “Too cold and the beer loses aroma. Cask ale is just right.”
Once tapped there are maybe three or four days in which the beer stays fresh. Each pint pulled allows oxygen into the once closed cask environment and that alters the flavor. An excellent cellarman can keep a cask fresh for up to six days, but that last pint will taste different from the first.
There are many appeals to cask ale. First, the temperature allows for aromas and flavors to present themselves as the brewers intended. Second, the natural carbonation leaves you feeling less bloated and thus more willing for another round. While no longer unique to the United Kingdom, real ale is still a source of pride in its homeland.
“There are few places where you can drink beers that are not too strong but are still loaded with flavor,” said Jeff Bull of insidebeer.com and Beer Lover’s Britain. “Beers of 5 percent alcohol and above are all very well in moderation, but a pint of British bitter at, say, 3.7 percent, is a real treat, a beer that oils the wheels of conversation and doesn’t inebriate so quickly. When cask conditioned too, it has a wonderful fresh flavor, a refreshing natural effervescence and great complexity. It’s one of our great gifts to the brewing world.”