Cask Ale: Tips from Pros
Cask ale, also called “real ale,” is naturally carbonated through a secondary ferment in the barrel. The beer is not filtered or pasteurized and is dispensed without the use of gas. We’ve pulled together two pros with years of casking experience to help get you on your way to brewing great cask-conditioned beer.
Brewer: Garrett Oliver, Brooklyn Brewery in Brooklyn, NY
Cask beer is the first beer that I fell in love with, so it remains at the root of my fascination with brewing. Cask beer is a slow drink in an age that too often demands speed over quality. It’s an art form as much as a science, and that’s a beautiful thing. We produce cask beer every week, some of which we’ll age for a year or more. Casking is something we do entirely by hand, and for New York City it’s a pretty Zen activity. And that’s a good thing unto itself.
When done properly, cask beer is more nuanced, layered and subtle than the vast majority of kegged beer. This is especially true of low-gravity ales, which can transform into elegant and revelatory beers, even at 3.5% ABV. There’s a creamy softness to the texture, yeast-driven fruit flavors come forward, and the whole mouthfeel is different and better married.
At Brooklyn Brewery, we cask condition any beer we make that has a British-style background, including some of our Brewmaster’s Reserve specials. I’ve recently had a number of Belgian-style cask beers in the UK, and although they were interesting and adventurous, I’ve yet to find one convincing. That said, some German lager styles do well, primed a bit more heavily to give an “Ungespundet” (mild effervescent) character. Those are often served a bit hazy.
Cask conditioning and service produces a beer that is less carbonated and served cool rather than cold. As a result of this and the churning caused by the beer engine, hop bitterness seems much lower in cask versions of any given beer. The beer’s sweet and fruity elements also come forward. So when we brew a beer specifically for cask, we’ll adjust the bitterness upwards to provide a better balance.
We use steel casks. Wood casks are cool looking, but they confer no real advantages as you do not want to impart wood flavors from the cask. Plus, steel can be sterilized, which is also important. When we want to impart wood flavors, we barrel-age, usually in bourbon oak, but that’s very different than casking.
Consistency is, in a way, the issue in cask beer. One thing that many American brewers don’t understand is that traditional British cask beer is supposed to be absolutely, utterly bright. No haze whatsoever. Cask beer should also be frisky (not fizzy) and cool, not warm and flat. We’re Americans and we can do as we please, but if your beer is flat or hazy, it’s definitely not traditional cask beer. We ferment our cask beer out to the end of fermentation and then prime the beer with sugar, finings and new yeast for conditioning. This, with proper cellarmanship, produces a consistent result.
We usually give our beers at least a week in cask to finish the secondary fermentation. Our Best Bitter prefers about 10 days for the malt flavors and fruity yeast flavors to deepen. IPA, on the other hand, likes to get out there fast; five days is fine. This gives the best and brightest hop flavors.
At home, unless you have a cask breather system, you really should drink the cask in a single evening. So you might want to have a party! A breached cask can sometimes last another day, but not more than that. And give it time on the stillage to drop bright — 24 hours is usually not enough. It’s a hobby and you’re not under commercial pressure, so why not take your time? Three days in place, and you’ll have far nicer pints.
Brewer: Hugh Sisson, Heavy Seas in Baltimore, MD
Cask beer is draft beer at its highest expression. Unfiltered, softly car-bonated, rounded and complex. It
is naturally and gently carbonated in the cask — much like Champagne is carbonated in the bottle. It is a
very artisanal approach that we just plain like.
We use the same base beer for our cask-conditioned beers as we do for our “regular” beers, we just pull it before it is filtered. Oftentimes we may give it extra hops or wood chips depending on if we believe the style will support it.
We have both wood and stainless steel casks, but they are mostly stainless steel. The wooden casks are expensive and really fragile — so they are a challenge — but they do add an additional flavor nuance. I think we own eight wooden casks and around 600 stainless ones.
In the cask, it usually takes about five days until the beer is carbonated through secondary fermentation. It may require a bit more time for some of the bigger beers, or if we are dry hopping it is better to give it a few more days.
One tricky thing with cask conditioning is that it is more difficult to reproduce the same exact beer every time. Certainly, cask conditioning is not an exact science. We are pretty consistent, but there are definitely small variances between casks. It is “live” beer after all.
When it comes to advice for homebrewers exploring cask conditioned beer, the fact is that most homebrewers are already bottle conditioning so they already are experiencing “real” ale.
The most difficult part of conditioned beer for homebrewers probably is getting the carbonation level right. You can over-carbonate and blow out the bung (which is messy as hell) or you can under-carbonate, which will result in a beer that is dull.
