One of the real pleasures of home brewing is in recreating styles of beer that are extinct, virtually extinct or at the very least, unavailable in your region of habitation. One of the cult classics of the beer world that fits into these categories is cask conditioned ale and its more restrictively defined sister, real ale. These were the classic pub beers of Great Britain, that with the rise of the mega breweries of the mid to late 20 th century, were largely extirpated from their homeland in favour of bland, fizzy commercial shlock ales and more recently, Eurolagers. However, as most of us know, with the rise of CAMRA, Campaign for Real Ales, there has been a resurgence of interest and demand for real ales, although it is unlikely to ever approach it's former popularity.
To the mega brewer, cask conditioned ales and real ales are a real pain. There are a number of reasons for this. Firstly, because they are not served with the "benefit" of CO2 they have a very limited lifespan, only a few days after being tapped. Limited shelf life is a primary concern for modern brewers. Secondly, the beers required knowledgeable publicans who understood beer and knew when to tap it and how to handle it. With the destruction of the Ma and Pa locals, the person serving the beer was likely to be an ignorant bar rat with no understanding of the beer. This forced the breweries to have to take on the job of conditioning the beer themselves. This meant keeping beer on their premise that they had already paid tax on and it meant hiring workers to do that job. Both undesirable for big breweries. Finally, real ale does not travel well. The old rule of thumb was that you could not ship a real ale farther than the distance a team of horses could travel to and return in a day.
Obviously, for mega brewers intent on capturing national markets, sales districts in the order of a 100 sq. km were not going to be economically feasible. So real ale was steadily weaned out and replaced by keg conditioned ales and bottles.
To capture a national market British brewers have followed a trend of reducing product diversity, focusing on a few national brands. Much of the beer has been dummied down in terms of original gravity of which a significant portion now comes from sugar or molasses.
To fight this loss of product quality and to preserve the heritage of the British brewing industry CAMRA has lobbied both the brewing industry and government. The pressure the brewers to maintain what few real ales and cask conditioned ales they still produce and they lobby the government to prevent takeovers of small and regional breweries by national and international corporations.
What are real or cask conditioned ales?
Because cask conditioned beers are exposed to oxygen once they are tapped, they have a very limited lifespan - often measured in days. The beers will become progressively more dull and tangy. Because the beers are served so young, usually within 10-14 days of being brewed, they have a fresh character highly prized by lovers of real ale. A beers unique characters tend to stand out as they do not have a chance to blend through aging. Again, to mega brewers trying to appeal to a mass market, they do no want their products to have unique flavor characteristics - another reason for the demise of real ale.
Because cask conditioned ales are served from their secondary fermentation vessel they typically do not have a big hop aroma. British brewers prefer to dry hop for hop aroma, but adding hops to the serving vessel is problematic as they can plug up the equipment and they are hard to clean out.
To my understanding "cask conditioned ales" are a broader class that includes within it "real ale." Cask conditioned ales are any ale in which the beer undergoes its secondary fermentation in the cask it is to be served from. That is, it is literally cask conditioned. Real ale is a cask-conditioned ale in which the cask is made of wood. That simple difference is important because wood will breath whereas stainless steel tanks will not. Air and microbial activity will have a more pronounced affect on real ales giving them a unique flavor profile compared to other cask-conditioned ales. All cask-conditioned beers are supposed to be served only under the influence of air. Carbon dioxide tanks are not allowed in the production of traditional cask conditioned ales. All the carbonation in the beer comes from the secondary ferment in the conditioning tank. Thus carbonation levels of cask -conditioned ales are going to be much lower than in keg beer conditioned with CO2.
This is one of the reasons why traditional British Bitters, no matter how bitter or flavored with hops, are allowed to have little to no hop aroma. The one exception was India Pale Ale. In those beers the benefits of hops antiseptic quality to enhance d product stability on the long sea voyage outweighed the hassle of their serving and cleaning problems. However, most real ales have a relatively low hop character and thus are classically: ordinary and best bitters, milds, Scottish ales, and at the high end, old, strong and scotch ale.
Also, since these beers are served right from the conditioning tank they cannot be filtered. Clarification is done by use of isinglass. The lack of filtration lends itself to maintaining more of the ales original character. However, mega breweries often use sterile filtration, done at an extremely small pore diameter, to enhance product stability. The cost of this practice however is that it also filters out many flavor compounds. To a schlock mega brewer this flavor reduction is a small price to pay for increased shelf life.
From the above we can derive some of the flavor profile of typical cask conditioned ale. It will be low in conditioning and will have a fresh, clean rich taste. It will lack the crispness that comes from CO2 acidity, but on the other hand its flavors will not be masked by the carbonation level. It will most likely be balanced towards the malt and will have only a light hop bouquet, if any. Further, as these beers are conditioned at cellar temperatures, they will be served at around 55 F (13 C). This relatively warm temperature, compared to modern bar serving temperatures, allows for maximum beer flavors to come through. In a word, these will be the freshest, most flavorful malt dominated ales possible.
Home-brewed Cask Conditioned Ales
Since there is no such thing as a bottle conditioned cask-conditioned ale, those of you without a keg are out of luck. Those of you who have a kegging system have the opportunity to recreate these classic beer styles. They are not at all difficult to do and you can adjust the level of "authenticity" to suit your own brewing preferences.
Malts
You want a malt that is going to clear easily and this requires a well -modified malt with a low protein level. Our locally available Westcan Malt works just fine.
Conditioning
Start your primary ferment pretty much as normal. Let the beer go until the yeast breaks from the surface or your airlock pops once every 15 seconds. You might want to let the beer have an extra day just to make sure it is fermented. This is because the next thing you ideally want to do is stick the primary in a fridge for 3-5 days. This forces much of the yeast out of suspension and helps clarify the beer. Remember, you are going to be serving from your secondary, so it is desirable to get rid of a lot of sediment and yeast before racking into the tank. The fridge does not have to be really cold. Many brewers cool to only 50 F or 10 C. However, I find that 45 F works very well.
After the beer has cold conditioned rack it into your keg and gently stir in your finings. I prefer isinglass as I find it rapidly gives very clear beer and it settles out fairly well to the bottom of the tank. I gently rock or bang on the container every two days or so for the first week to knock the isinglass off the sides of the tank and ensure that it all settles to the bottom.
In terms of conditioning there is some controversy at this point; and so here you have an opportunity to make some decisions about how much of a purist you are going to be. Hard core real ale purists demand no CO2 in the tank other than what comes from the secondary ferment. To handle this situation you will need to make or acquire a rack to hold your keg. You need to tip the keg at an angle with the top down and with the short (normally gas in) tube at the bottom and the long (normally beer out) tube at the top. You will then serve the beer by connecting your cobra hose or beer engine to the short tube to let your beer pour out under its own pressure. You will need to periodically release air into the keg by depressing the long tube valve. In this way you are truly making and serving traditional cask conditioned ale. It will be exposed to the air within a few days and will develop some classic oxidized flavors prized by aficionados. Also, your sediment will settle near the lid of the keg and your short tube will likely be above the sediment, yielding clear beer from the first pour. The disadvantage of this purity is that your beer will go bad within a few days to at most a week. Unless you can consume 5 gallons of beer in a week, (big family, a big party, you're an alcoholic) this is probably not the best choice.
Faced with a relatively low demand for real ales modern brewers will now often put a little corn sugar into the secondary. This allows a thin blanket of CO2 to form over the beer and improves shelf life. It can also yield a bit higher level of carbonation which is more likely to appeal to the modern beer consumer. After much whining, but faced with the reality of losing even more beers to keg versions, CAMRA has relented on this practice and will now accept that a beer can be called cask conditioned if it is conditioned with a bit of sugar.
However, they will still not accept a brewer using a CO2 tank to put a thin layer of CO2 into the cask. To my mind this is ridiculous. There is no effective difference, except to produce less sediment (desirable), between using sugar to condition a beer and using a CO2 tank. Both will carbonate a beer and both will produce a protective blanket. In fact, by injecting CO2 into the tank you can better control your gas level and keep it low. A number of breweries are arguing this point.
For myself, I follow the latter method. Product stability is more important than absolute purity of purpose. I set my regulator to the lowest point where I can inject CO2 into my tank. I then add my finings, pump in some gas and let it settle. Then I release the pressure, open the tank and rack in the beer beneath the gas cloud. I then pump in the gas again and let the beer sit until it is conditioned.
I let my casks condition about a week before I start to consume the beer. You can see that from the time you brew to the time you consume is about 14 days, or about 2 weeks faster than normal keg conditioned beer. A real advantage of cask -conditioned beer is that you can whip one up on pretty short notice.
Hopping
As I mentioned above, most cask-conditioned ales are balanced towards the malt so hop bouquet is not a necessary character of these beers. However, there are a number of ways you can get hop bouquet. Firstly, you can late hop in the last 5 minutes of the boil. This produces a soft hop bouquet, similar to Eurolagers, which would seem to be very appropriate for cask conditioned ales. Secondly, you can put leaf hops into your hop back but this tends to be inefficient on a homebrew scale. Thirdly, you can dry hop in your primary for the 3-5 days the beer is in the fridge. As ferment activity will be very low you should not have the risk of the hops plugging up the airlock. I would use pellet hops as they will "dissolve" into the beer. Leaf hops are likely to just float on the surface. Lastly, you could put the hops into a hop sock and throw it into the cask. It has been suggested that a very large tea ball could be partially filled with pellet hops and put into the cask. I like that idea but have not yet tried it. Leave space in the ball as the hops will expand when soaked with beer.
That's all there is to making cask conditioned ale using homebrew methods. The practice can easily be adapted by anyone who has a kegging system. A fridge may not even be necessary if you brew them during the winter and you have a cold room in your house.