Cask ale
From Wikipedia, the free encyclopedia
Cask ale or Cask Beer is the term given in the US to unfiltered and unpasteurised beer which is conditioned and served from a cask. A fuller term (used more frequently in the UK) is "Cask-conditioned beer" (which reflects the conditioning, not just the method of dispense), but this term also implies that the beer is served without additional nitrogen or carbon dioxide pressure. Such beers are also referred to as Real Ales, a term coined by the UK's Campaign for Real Ale, often now extended to cover bottle-conditioned beer.
Contents |
[edit] The history of cask beer
- See also: History of beer
The term cask merely refers, of course, to the container in which the beer is stored. It comes from the Spanish cáscara which means tree bark, in the sense that the bark surrounds and holds the tree in the way that a cask surrounds and holds the beer. The Histories of Herodotus, written in 424 BC, refers to “casks of palm-wood filled with wine” being moved by boat to Babylon, though clay vessels would also have been used. Stout wooden barrels held together with an iron hoop was really something the north European Celts developed during the Iron Age for storing all manner of goods. But whether the “cask” was made of clay, palm-wood or oak, whether it was a barrel, a pot or a storage jar, all had one thing in common - they all contained unfiltered, unpasteurised beer. Put simply, cask ale is the original method of storing and serving beer - the history of cask ale goes right back to the origins of beer itself. Over the centuries other methods have been developed for preserving and storing beer but this ancient method is still used, particularly in Britain.
That is not to say that this traditional serving method hasn’t come under threat. Bottled beers were commonplace by the 17th century for the well off who didn’t wish to drink in public inns, or who wanted to take a beer with them when fishing. Such as the famous story of Alexander Nowell, the Dean of St. Paul’s, who, in 1568, left his bottled beer by the river bank, and upon returning a few days later discovered the bottle opened with a bang and that the contents were very tasty. But while the middle and upper classes could indulge themselves with such expensive luxuries, the ordinary folk continued to drink their beer served direct from the cask. The famous ale that was shipped to India was delivered in casks, and only transferred to the bottle for the civilian middle classes - the troops drank their beer the same way they drank it back home - from flagons filled direct from the cask. But as beer developed and became paler and lower in alcohol, so it became more difficult to keep it fresh tasting in the cask, especially in countries with warmer climates. By the late 19th century commercial refrigeration and Louis Pasteur’s flash heating method of sterilisation prolonged the life of beer. In Britain’s cooler climate these methods did not catch on. At least, not immediately.
Of course not all beer in mainland Europe is pasteurised - there are plenty of examples of unfiltered, unpasteurised beers, but these will commonly be served from a chilled container under pressure - a keg.
The keg was introduced in Britain in the 1950s as a means for breweries to keep the beer from going stale. Unlike a cask which allows air in, the keg is a sealed container. In order to get the beer out of the keg and into a customer’s glass, it needs to be forced out with gas pressure. By the early 1970s most beer in Britain was keg beer - filtered, pasteurised and artificially carbonated. Some of the last remaining natural beers in the world were about to disappear forever. Though rare examples of natural beers could still be found in the farmhouse beers of Northern Europe and the maize beers of South America for example, in essence the last great stronghold of natural beer was about to be wiped out. And that’s when the Campaign for Real Ale (CAMRA) stepped in to save what they came to term Real Ale.
[edit] Real ale and bright beer
CAMRA’s official definition of Real Ale is, “beer brewed from traditional ingredients, matured by secondary fermentation in the container from which it is dispensed, and served without the use of extraneous carbon dioxide.” It’s an awkward definition that, like Germany’s Reinheitsgebot, can be quite restrictive. However, the term “traditional ingredients” is designed, like the Reinheitsgebot, to prevent artificial preservatives or cheap adjuncts or chemicals from being used in the making or storing of the beer. So even if the American Budweiser was served straight from a cask, it would not be considered real because of the rice and other non traditional ingredients. The heart of the definition is the “matured by secondary fermentation in the container from which it is dispensed”. If the beer is unfiltered, unpasteurised and still active on the yeast, it is a real beer - the container can be a cask, a bottle or a tin can, it doesn’t matter. If the yeast is still alive and still conditioning the beer, it is “real”.
All cask ales have finings added which drag the yeast to the bottom - when the finings have cleared the beer it is said to have “dropped bright” and the beer will look clear rather than cloudy. But if a beer has been filtered, or has been cleared of yeast by using finings, and then "racked" — transferred to another container, this is “bright” or re-racked beer. Bright beer is essentially unpasteurised beer which has been cleared of yeast and placed in a different container. It no longer sits on the yeast. As such, strictly speaking, it is not real ale because it cannot continue to ferment in the container in which it now finds itself.
The main restrictive element in the definition, and the one that causes conflict with pub landlords and American style brew pubs is the last phrase - “served without extraneous carbon dioxide”.
[edit] Managing carbonation
One of the landlord’s jobs is to tap the cask and let the excess gas escape. However, and here we come onto the controversial “cask breather” issue, once a cask has been tapped, the beer starts to come into contact with oxygen - and a beer in contact with oxygen has a limited life. The stronger the beer the longer it will survive, but for most ales with an ABV in the low 4% region, three days is typical. If the pub doesn’t have a high turnover, or if a beer is not popular, such as dark milds, three days will not be enough to sell all the beer in the cask. A cask breather allows a small amount of CO2 to replace the oxygen in the cask. Not enough CO2 to put any pressure on the beer so that the CO2 enters the beer or pushes it up to the bar - that’s “top pressure” -, but just enough “blanket pressure” to keep the beer fresh tasting for longer. Just long enough, in fact, for the landlord to sell all the beer in the cask.
The use of cask breathers is considered “extraneous carbon dioxide”, so CAMRA does not endorse this method.
[edit] Preparation for drinking
Cask ale is brewed in the same manner as keg beer. The same brew run could be used to make cask, keg and bottled beer. The difference is what happens after the primary fermentation is finished and the beer has been left to condition. While pasteurised keg and bottled beers are then subjected to filtering and flash heating, the beer for the cask is simply placed in the cask in its natural state. Finings, such as isinglass (the swim bladder of fish) or Irish Moss (a seaweed), are placed in the cask to drag down the yeast and clear the beer. Extra hops and sugar may also be added. The cask is sealed and sent off to the pub. In this state it is like a bottle conditioned beer, and like bottle conditioned beers the beer will continue to develop for a certain period of time. And like bottle conditioned beers the actual length of time the beer can survive will depend on the nature of the beer itself - strong, dark beers can last for months, light, delicate beers need to be tapped and sold quickly. The landlord will store the casks according to his knowledge of the beer. The delicate beers will be the ones he needs to tap first. The stronger beers will need longer to settle and mature. Some pubs have been known to keep very strong beers in a sealed cask for up to a year to allow them to fully develop.
When the landlord feels the beer has settled, and he is ready to serve it, he will knock a soft spile into a bung hole on the side of the cask. The major difference in appearance between a keg and a cask is that bung hole. A keg does not have a bung hole on the side. The majority of casks these days are metal, and at first glance look just like kegs. Even though there are still some wooden casks around, these are rare - in fact there are more plastic kegs around than wooden ones. Plastic casks are increasing in popularity because they are cheaper to buy and lighter to carry, though they don’t last as long. Beer casks come in a number of sizes, but by far the most common in the pub trade are those of 9 gallons (72 pints or roughly 41 litres) which is known as a Firkin and 18 gallons (144 pints or roughly 83 litres) known as a Kilderkin. N.B. These relate to the imperial gallon where 1 gallon (imperial) = 1.201 gallons (US)
The soft spile in the bung hole allows gas to vent off. This can be seen by the bubbles foaming around the spile. The landlord will periodically check the bubbles by wiping the spile clean and then watching to see how fast the bubbles reform. There still has to be some life in the beer otherwise it really will taste flat, but too much life and the beer will taste hard or fizzy. When the beer is judged to be ready, the landlord will replace the soft spile with a hard one (which doesn’t allow air in or gas out) and let the beer settle for 24 hours. He will also knock a tap into the end of the cask. This might simply be a tap if the cask is stored behind the bar. The beer will then be served simply under gravity pressure: turn on the tap, and the beer comes out. But if the cask is in the cellar, the beer needs to travel via tubes, or beer lines, up to the bar area.
[edit] Serving cask ale
A “beer engine” or handpump is used to siphon the beer upstairs. The beer engine is a half-pint (sometimes a 1/4 pint), airtight piston chamber - pulling down on the handle raises the piston which drags up a half pint of beer. When a cask is first tapped into the beer engine, or after the lines have been washed through, the pump needs to be pulled several times to clear the lines of air or water. The line will continue to hold beer, which will tend to go stale overnight, so the first beer pulled through will be bad beer, and this will be simply thrown away. Most pubs will pull through at least a pint of beer on each beer engine before they open, while others will wait for the first order of beer on that pump before pulling through. Experienced barstaff will serve a pint with two long, smooth, slow pulls of the pump handle, plus a short third just to make sure the glass is full.
If you peek over the bar at the spout from which the beer emerges you may notice a small flip tap and a short spout - this is normal. If you notice the spout is quite long with a hairpin curve this is a swan-neck which is designed to force the beer into the glass, agitating it so that a head is created and some flavour is reduced.
In some pubs a small device or cap is fitted to the end of the spout rather like a sprinkler at the end of a hose pipe. The device is known as a "sparkler". Like the sprinkler at the end of a hose, this can be twisted to regulate the flow of the beer. When the sparkler is tight, the beer is severely agitated resulting in a large head but a significant loss of flavour and mouthfeel. This is most common in the North of England. Many drinkers in the North prefer their beer this way - it is softer and creamier with less bitterness. Drinkers in the South tend to prefer their beer with a touch more bitterness, and a slightly harder mouthfeel.
A word of warning - some pubs will disguise a keg beer by having some form of imitation pump handle on the bar. If the barstaff have merely turned on a tap, or are just resting their hand on a very small handle with no pump action, then this is a keg beer - apart from some pubs in the North which use electric pumps on cask ale. If in doubt - ask.
[edit] How to tell the difference between keg and cask
Keg beers have got better over the years. It is possible for a fresh keg beer to be better tasting than a cask beer in poor condition. Also, and this may seem strange considering all the fuss made over the preservation of cask beer, it is quite common for someone who is unfamiliar with cask ale not to be able to taste the difference between cask and keg beer.
The famous warm temperature of cask beer in the summer months doesn’t apply all that often these days with temperature control units in pub cellars and the beer lines running through coolers. In fact, some pubs will run the cask ale lines through the lager chiller in order to get the beer below the maximum temperature required by Cask Marque, so a cask ale may end up as cold as a keg lager. This is rarely a good thing, because ale requires a cool rather than a cold temperature to reveal all its flavours. It can also disguise a far worse situation in which, although the beer in the glass is cold, the contents of the cask are rapidly turning to vinegar in the heat. Moderate cooling around the beer lines to maintain their temperature against the warmth of the bar is usually beneficial, but the beer must be stored at an appropriate temperature to begin with. In a well run pub the cask ale will be served at the appropriate temperature - cool, but not chilled.
The aroma of cask ale is fresher and more wholesome than keg beer. But the aroma of cask ale does not have the stored up impact of bottled beers - cask beer is beer which has already been exposed to the air for a couple of days, so there is not going to be a big impact when it is simply transferred to your glass. Typically the aroma will be released when it has warmed up slightly, and that will probably be when you are near the bottom of the glass. And no prickly oxygen tent aroma that comes with the extra CO2 used to give keg beer its “life”. All you will smell is natural, fresh beer - and the difference is like sniffing artificial fruit flavourings compared to sniffing the fresh fruit. The artificial flavourings will be pleasant and intense, while the fresh fruit will be very delicate, sometimes slipping away. Aroma, it has to be admitted, is not one of the high points of cask ale - but if you prefer scents that are delicate, exquisite, fresh and natural, then you will enjoy the bouquet of cask ale.
The flavour of cask ale is similar to the aroma in that it is delicate and fresh, but unlike many bottled beers the flavour of cask ale is more noticeable than the aroma. The aroma is often very slight, even non-existent at first, but the flavour makes up for that. Obviously the intensity of flavour depends on the beer style - a session bitter is not going to slap your taste buds in the way that a golden ale or imperial stout will - but a cask ale in good condition will have the flavours defined rather than muddled. CO2 bubbles in themselves have little flavour, so a mass of those bursting against your tongue will prevent the beer itself from making contact. With cask ale there is little carbonation, so more of the flavour compounds will be in contact with your taste buds. You should be able to clearly note the fruity sweetness up front, the balance in the middle and the bitterness in the finish. The flavour profile of a cask ale is much more noticeable than a keg or bottled beer. Bottle conditioned beers will also have this noticeable flavour profile, but they need to be prepared and conditioned in advance - that is, the bottle needs to be opened and allowed to settle for a few hours. With cask ales the conditioning has been done for you (and hopefully done by someone who knows what they are doing!).
The most important aspect of cask ale is the mouthfeel. It should not be fizzy. If your beer is fizzy then it’s either a keg beer or it’s a cask ale that’s been put on too soon. If you are used to carbonated drinks - keg beer, bottled beer, sparkling water, cola, etc - the mouthfeel of a cask ale may seem a little strange - even flat or boring - at first. There are some people who don’t even notice the mouthfeel. If they are just drinking the beer without paying attention - maybe they are chatting away, or maybe they are trying to catch the aroma or flavour of this cask ale they have heard so much about - the mouthfeel will pass them by.
[edit] See also
[edit] External links
- BeerAdvocate Cask Conditioned Ale / Real Ale Group
- Real Ale for New England, by Todd & Jason Alstrom
- The Truth About Cask Ale, article by SilkTork
- About Real Ale, article by CAMRA
- A Question of Carbonation, article by SilkTork
- Brewin' Beagle, Chicago cask ale specialists
