Welcome
Cask beer or cask conditioned ale is the term for unfiltered and unpasteurised beer which is conditioned (including secondary fermentation) and served from a cask without additional nitrogen or carbon dioxide pressure which are used in ‘keg’ products such as Draught Lager or ‘smooth’ bitters (Worthington Creamflow/John Smiths Extra Smooth). Cask ale may also be referred to as real ale, a term coined by the Campaign for Real Ale, often now extended to cover bottle-conditioned beer as well.
The Cask v. Keg Argument
The essential differences between a traditional cask and a keg are that the latter has a centrally located downtube and a valve that allows beer in and gas out when filling and vice versa when beer is dispensed. Also kegs have a simple concave bottom whilst the barrel or cask design allowed sediment to be retained in the cask. This aspect of keg design meant that all the beer in the keg was dispensed which therefore required that the beer be processed by filtration, fining or centrifuging, or some combination of these, to prevent sediment formation. Lastly, kegs have straight sides unlike the traditional barrel or cask shape. In order to get the beer out of a keg and into a customer’s glass, it is forced out with gas pressure.
By the early 1970s most beer in Britain was keg beer, filtered, pasteurised and artificially carbonated. This change was largely driven by the customer’s dislike of sediment in his beer. However, most British brewers used carbon dioxide for dispensing keg beers. This led to beers containing more dissolved gas in the glass than the traditional ale and to a consumer demand for a return to these ales some years later. By contrast, in Ireland, where stout was dominant, the use of a mixture of carbon dioxide and nitrogen for dispensing prevented the beer from becoming over-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. In 1973 the Campaign for Real Ale (CAMRA) was founded in Britain to save this dying industry and what they came to term “real ale”.
Preparation
Broadly speaking, cask ale brewing starts the same as that of 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. Typically keg and bottled beers are either sterile-filtered or pasteurised or both, but beer destined for cask is simply ‘racked’ (poured) into the cask in its natural state. Isinglass Finings are placed in the cask to assist ‘dropping’ the yeast giving a clear beer. Extra hops and priming 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. Also like bottle-conditioned beers, the length of time the beer can last in the cask will depend on the nature of the beer itself: unopened, stronger beers can last for months; light, delicate beers need to be tapped and sold quickly. Stronger beers may also need longer to settle and mature. Some pubs have been known to keep very strong beers in a sealed cask for a year or more to allow them to fully develop.
The major difference between a keg and a cask beer is the preparation after delivery. A keg does not have to go through the following process, it can be dispensed on the day of delivery. The cask however will be layed on its side on the stillage to allow the sediment to settle in the belly of the barrel, hence the rounded shape of casks, this usually takes about four days. When the landlord feels the beer has settled and all the sediment has dropped into the belly, they will knock a soft spile into the shive on the top of the laying cask and hammer a tap into the keystone on the front of the cask. The majority of casks these days are metal, and look similar to a keg, but with the rounded traditional barrel shape (kegs are often straight-sided). Even though there are still some wooden casks around, these are rare; in fact there are more plastic casks 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, they are also less likely to be stolen as they have no melt-down value. 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.
The soft spile in the shive 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 will taste flat. 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 stops the beer from working or foermenting further). The beer is now ready to be served simply under gravity pressure: turn on the tap, and the beer comes out. But as at The Horse Chestnut, the cask is in the cellar, the beer needs to travel via tubes, or beer lines, and be pumped up to the bar area, normally using a handpump also known as a ‘beer engine’.
Pouring The Pint
A “beer engine” or handpump is used to siphon the beer upstairs. The beer engine is a 0.5 imp pt, 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. Experienced bar staff 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. We at The Horse Chestnut use a spout which 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.
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”. Different colour sparklers have different sized holes and therefore will force the beer through at different speeds creating more or less ‘head’, the smaller the holes the greater amount of head created. 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.
What Defines Real Ale?
Those seeking authentic real ale should be aware that some pubs will disguise a keg beer by having some form of imitation pump handle on the bar. If the bar staff 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. Exceptions are some pubs in the north which use electric pumps or the pubs in Scotland that use traditional air-pressure founts5 on cask ale. Asking the staff will usually clarify this.
Real ale is the name coined by the Campaign for Real Ale (CAMRA) in 1973 for a type of beer defined as “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”. [1]2 This is a definition that, like Germany’s Reinheitsgebot, can be seen as quite restrictive3. 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. 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; it is irrelevant whether the container is a cask or a bottle. If the yeast is still alive and still conditioning the beer, it is “real”.
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. 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.