Cask ale: what's all the fuss about?

To celebrate Cask Ale Week, we've asked the three-time winner and current Beer Writer of the Year, Ben McFarland, to give us the low-down on the burgeoning trend for craft ales. In this piece, he explains what craft ales are and how they are brewed.

Looking for the second piece? Read it here: Cask ale: who's drinking it and why

No one wants to prick the nation's swelling bubble of post-Olympic pride and patriotism but Danny Boyle got it all wrong. During the Olympics' opening ceremony, the ultimate symbol of Britain's entrepreneurial verve shouldn't have been Sir Tim Berners-Lee, inventor of the internet. No, rather than the nation's biggest IT nerd, Boyle should have served up a freshly poured pint of cask ale.

Deep down, he knows that. And now you do too.

What is cask ale?

According to the misinformed little book of cliches, cask ale is a warm, flat and insipid liquid legacy of a grim, grey past gulped by doddery coffin-dodging men with dubious personal hygiene, dress sense and social skills.

This is, of course, not true.

Cask ale is beer at its most natural and untouched. If beer was bread (which it pretty much is, in liquid form) cask ale is a warm, crusty fresh-out-of-the-oven bloomer while mainstream, mass-marketed lagers are the kind of crustless, soulless sliced-white that, pumped full of additives and preservatives, take a century to go stale.

Also known as cask-conditioned beer or 'real' ale, cask ale is beer that undergoes secondary fermentation in the barrel. Brewers of cask ale don't interfere with it, they don't filter it and they don't pasteurise it. All they do is brew the beer with natural ingredients (hops, barley, water and yeast) and then put the fresh live beer straight into the barrel where, still in unfinished form and containing lots of lovely fruity residual yeast, it remains alive and kicking until it lands in your glass.

Cask conditioning is to beer what the méthode champenoise is to wine. While champagne evolves in the bottle, cask ale matures and ripens in the barrel; the live yeast nibbles away at the sugars, turning them into alcohol and creating carbonation, rounds off rough flavour edges and brings greater depth of character.

Nearly all the action occurs in the pub cellar. Having arrived from the brewery and been laid down in the cellar, cask ale needs to settle down, following the rigours of travel. It needs cool (13-14C) and it needs a bit of calm (of between 24 hours and two weeks).

During this time, the cask of real ale will be tapped with a small spile to allow excess carbon dioxide to escape, the cask will then 'drop bright', the yeast settling at the bottom of the barrel, and the beer will become clear.

Each cask ale is different: some are chilled-out characters while others are more boisterous and take longer to get ready. A skilled cellarman/publican will know how long to leave each beer before it reaches its perfect peak, making sure it doesn't lose its natural effervescence.

This is the art of a cellarman; an age-old craft of magic, science and human judgment that can make all the difference between a dodgy pint and an exquisite elbow-bending epiphany.

Once the beer is deemed ready, it is then drawn up, using a hand-operated hydraulic pump, from the cellar into the glass or, if you're a bit old school, a dimpled jug.

The beer should never be flat nor should it be frothing all over the place like laundry soap. It should be gently effervescent, displaying a light prickle on the palate and topped with a lovely white head, the size of which depends very much on where you're drinking it.

Geordie drinkers, for example, like it large; Yorkshire drinkers like a tightly knit top while southerner landlords layer a thin frothy head on a pint of real ale.

Each will get rather annoyed if it's served otherwise.

Some publicans put a sparkler on the pump nozzle to increase the effervescence. Purists have a problem with this but most people don't mind as long as the beer tastes lovely.

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• 10 new, rare or exclusive cask ales

Where is cask ale sold?

Britain. Cask ale is almost exclusively British. Other nations try to make replicate real ale but, unlike cricket and football, they've never bettered the inventors. The Americans don't have the patience, the Australians don't have the climate and the Belgians do their own thing.

Cask ale can only be drunk in the pub. The nearest you can get to cask ale at home is bottle-conditioned beer which, containing yeast, re-ferments in the bottle. While bottle-conditioned beers can be sensational, the genuine cask ale experience can only occur in the pub, making it an inherently social drink that brings people together.

Cask Ale Week runs from 28 September to 7 October. For more information, visit caskaleweek.co.uk.

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