Imbibe: When did you first get into cask beers?
Greg Engert: My first introduction to cask beer came while I spent a year studying at Trinity College in Ireland. I had the chance to travel a bit around Europe during that time, and that’s when I got my first taste of the stuff. But I didn’t really get into it until a few years later when I took my first industry job at the Brickskeller in Washington, D.C. The bar has since changed hands, but it was the beer bar in the U.S. for a long time, and it was there that I started to learn about the tradition, history and nuances of cask beer. When I left and joined the Neighborhood Restaurant Group, I started to realize there were people who would drink as much cask beer as I could offer them—it was then that I developed an insatiable appetite for real ale and decided to implement strong cask beer programs at all of our bars and restaurants.
So it’s fair to say you’re appreciation for it has grown over the years?
Definitely. It seems to me that cask ale—on account of being unfiltered, unpasteurized, naturally carbonated through fermentation alone, and served at cellar temperatures—is the purest expression of the brewmaster’s intent. Each and every flavor developed by the brewing and conditioning process is 100% natural, and not one element has been stripped from the brew.
For those who aren’t familiar with the style, can you offer a quick rundown on what exactly qualifies a cask beer, or “real ale” as it’s often called?
Cask beer is basically any style of beer that can go into a cask. Whereas standard draught or bottled beer goes into some kind of stainless steel conditioning tank after fermentation, cask beer goes into smaller wooden casks—also called firkins—where the brewer then re-ferments it either by adding a younger, still-fermenting version of that same beer, or by adding a little bit of sugar and yeast to kickstart a second fermentation in the cask. It gets sealed, and as it continues to ferment, pressure builds which naturally carbonates the beer and gives it a gentle, creamy effervescence that’s subtler than kegs that are force-carbonated. They’re served at cellar temperature—so definitely warmer than regular draught beer—and instead of being pushed through the beer line, they’re drawn to the glass via a hand pump, which creates a vacuum that suctions the beer out of the cask without letting much of anything else in.
Speaking of temperature, why are cask beers served warmer than their draught counterparts?
Refrigeration was invented at the end of the 19th century, so before then if you wanted to serve beer at a temperature beyond ambient you’d place it into the basement where it would cool to cellar temperature and then pump it up to the bar. What’s great about this is that the warmth encourages evaporation, which releases more aromatics, so you get this wonderfully fragrant, less gassy, creamy beer that has nothing removed or added to it.
Any other notable differences between drinking cask ale and a regular draught beer?
Carbonation and temperature are the two biggest things. Because cask beer is carbonated naturally through re-fermentation, the effervescence is much creamier and softer. Force-carbonated kegs have a much more aggressively sharp carbon dioxide quality to them, which accentuates bitterness and acidity, so when you drink a hoppy beer on cask the hops are gentler and not as astringent or as intense as force-carbonated draught beer. Temperature has a similar affect, so the colder a beer, the more bitter it seems. Really, when you taste hoppy beers on cask they’re a complete revelation—they’re much more mildly carbonated and hugely aromatic as well. One of my favorite things is when we have a beer on draught and cask simultaneously and can pour them side-by-side for guests. I wouldn’t say one is better than the other; it’s just a really cool way of experiencing how very different these two styles are.
What do you tell people who are about to take their first sip of cask beer?
I usually chat with them before they order it, because often people either come in not knowing anything about cask ale or with some negative association with it—mainly calling it warm and flat—because they had an experience where it wasn’t stored or served properly. We explain how cask beer is less carbonated and cold than what they’re used to, and how that affects the aroma, mouthfeel and taste. With the temperature and mild carbonation the flavors of the malt and hops spread all over the palate and you can really tease out subtler nuances that get lost in force-carbonated beers served at a colder temperature.
You’ve already mentioned that hoppy beers do well on cask—any other styles well suited to this serving method?
All sorts of English beers are amazing on cask as are darker, maltier beers that are low in alcohol—English milds and brown ales, as well as low-alcohol porters. Big beers on cask are fine, but with a low-ABV, sessionable beer on cask the combination of low carbonation and the slightly warmer temperatures allow for some really impressive and surprising nuances to come from a beer that’s presumably less complex because it’s low alcohol. A lot of people confuse intensity for complexity, but when you have a seemingly mild-flavored ale or lager of low ABV on cask it’s amazing how great they can be. Another unexpected beer amazing on cask are lagers. There’s a German tradition of kellerbier—an unfiltered, unpasteurized lager that re-ferments in the cask—that are completely different than what most people would expect because most people think of lagers as cold with big carbonation, but kellerbier offers these wonderful Old World flavors of grain and hop that are really delicious.
Any beers that don’t translate well in cask?
I don’t love Belgian beers on cask, as I find that Belgian beers need a little more carbonation. For me, the best way to serve a Belgian beer is re-fermented in the bottle because the fruit and spice qualities that are created during fermentation really need that huge natural effervescence to lift it out of the glass. On cask, with the milder carbonation, I think they come off a little flat and flabby and not as aromatic or complex.
Any favorite casks offerings?
There are tons! I love it when British breweries send over their stuff on cask—Thornbridge in phenomenal, Harviestoun is fantastic, as is Ridgeway. And sometimes we get very esoteric things like Wadworth, which you don’t really see over here at all. Domestically, we’re lucky in the mid-Atlantic to be surrounded by a lot of brewers heavily committed to cask ales, including Seven Seas—which actually sold the most cask ale in the country in 2011—Flying Dog, and Pratt St. Ale House out of Baltimore makes some really delicious English-style cask ale. But those are just a few that come to mind.