Tell me which of these two sentences rings most true, in your experience:
- Cask bitter is a lovely but antiquated beer style that hasn’t changed much in the past 50 years and is, sadly, dying in its home country.
- Cask bitter is a wonderful old tradition in Britain—more template than style—and is currently going through one of the most interesting evolutions in the world.
It’s not a trick question, honestly. For most Americans who come across a British-inspired bitter in the United States, it probably does feel like a taste of the past, so that first sentence makes some sense. For us, it’s like a style frozen in amber—less a taste of Britain, perhaps, than that of an earlier era in American brewing.
Meanwhile, cask ale—with bitter as its most popular style—has become a relatively marginal player in Britain. That doesn’t mean it’s unimportant there, and it still has its ardent fans. Yet a recent report from Britain’s Society of Independent Brewers pegs cask ale at just 9 percent of the country’s declining draft-beer market, and at 4 percent of British beer consumption overall.
It wasn’t always like this. Two generations ago, when the independent brewing revival was just getting started, Americans jetted off to London to learn how to make British ales. The tradition was still lively, and an imperial pint of English bitter seemed like the essence of beer. Today, brewers are more likely to land in Prague or Munich to learn about pale lager.
Here’s the thing: They’re missing out on something. As British beer has fallen out of favor here, American brewers have missed a quiet revolution—and this is where that second sentence above comes into focus. Classics such as Timothy Taylor’s Landlord, Fuller’s London Pride, and Harvey’s Sussex Best are still around, of course. But pubs are pouring them next to a new generation of bitters that harness the zingy flavors of New World hops—and British hops bred to compete with them—as well as the techniques that American IPA brewers have developed to infuse them into beer.
These beers rest on a familiar foundation of English malts and yeasts, but they feature modern hop varieties and techniques that add bright, fruit-forward flavors that meld perfectly with their base. They are purpose-built to be sessionable at around 4 percent ABV, and they are harmonious, full, and balanced—a trick that comes into focus when served via cask, a technique Americans have nearly forgotten.
This is one of the most exciting developments in the brewing world, and these beers are accomplished, remarkable little gems.
And Americans have no idea they exist.
It’s the Cask
This may be controversial, but stick with me: The more important element of cask bitter is the cask, not the bitter.
To see why, you need only to taste that classic formula of heirloom malts, English hops, and yeast on cask and from a keg. When done well, cask conditioning is an alchemical process that transmutes ordinary beers into something really special. Naturally carbonating the beer in this way leaves it less fizzy, but it also makes it silkier in texture. It encourages the flavors and aromas to blossom, magnifying their impact. Further, the subtle flavors blend into an alloy—bready malts, fruity yeast, earthy-sweet hops, and a minerality from the water all play their roles.
Perhaps this is why cask bitter appeared to be in stasis: It didn’t need to evolve. Outside the pubs, however, the world did. In Britain, craft brewing followed the United States by a couple decades, and many newer breweries followed the American model. They helped to create a taste for punchier hops—and they put pressure on the old bitter formula to respond.
Traditional ale breweries began experimenting with these hops, which often worked nicely alongside their classics. Newer breweries, meanwhile—besides embracing 7 percent IPAs with massive intensity—also began experimenting from the other direction, rediscovering their historical roots via session-strength cask ales.
In either case, the beer engine is the common ground—the terrain that dictates what kind of beers can be served with the most success. Those that have emerged are purpose-built for cask, at traditional cask strength and with traditional balance, but they get much of their character from brighter, more fruit-forward New World hops.
Classic bitters, but different.
“Juicy” Cask Bitter
In Manchester, England, the Marble Arch is not an obvious venue for wild, countercultural experimentation. It’s a Victorian pub that dates to 1888, a longtime darling of the Campaign for Real Ale and beloved by regulars who keep the casks moving. In 1997, when the owners decided to expand operations and start a brewery, they brewed classic cask ales. The anchor was a house bitter.
Before long, however, they were experimenting with American hops—tucking them in here and there in volumes that wouldn’t frighten the locals. It took a while, but eventually they transitioned to using mostly modern, New World hops, but always via the medium of cask-conditioned ale. Marble has been one of the most important breweries in this country-wide transition.
Head brewer Joe Ince explains Marble’s philosophy, offering a mission statement of sorts for making modern cask ales: “We have a two-pronged philosophy: A holistic approach where the combination of ingredients should outweigh the sum of those things separately. And, in a basic way, less is more.”
Their pub ales now use only New World hops, but “you can’t dry hop a 3.8 percent [ABV], 1.010 SG beer at 10 grams per liter,” Ince says. (That would be 2.6 pounds per barrel, or a bit less than 7 ounces per five gallons.) “There’s just nothing there to hold the hop flavor. So, instead, make smart choices with what hops you’re going to use and when in the process you want to add them.” Their Manchester Bitter is 4.2 percent ABV; they hop it with Comet, CTZ, and Ekuanot.
Just a mile down the road, Track Brewing launched about a decade ago with a very different approach. They focused on big, bold hop flavors at a moment when British beer drinkers were falling in love with them. Like so many craft breweries, however, they eventually returned to their roots and began exploring cask. Their best-known beer is Sonoma, 3.8 percent ABV and hopped with Citra, Mosaic, and Centennial. Hazy and pale, it looks and smells American—but it becomes something different when poured on cask.
Track head brewer Matt Dutton explains what makes it work. For a session-strength beer such as Sonoma, Track gets most of its hops via a whirlpool addition—at 176°F (80°C)—of about six grams per liter, or 1.5 pounds per barrel. They prefer whole-cone hops if they can get them. “The additional polyphenols and green matter help boost mouthfeel and make everything seem fuller,” Dutton says.
Those are the very elements many Americans try to subdue in their monster double-hazies, but in bitters they can be helpful. Track also dry hops at about a pound per barrel at terminal gravity, “to lift the aroma,” Dutton says.
Getting balance means laying down a proper malt foundation. Some breweries stick with heirloom varieties, but Track takes a more American approach. Most beers start with extra-pale malt. “This base is generally cut with a small percentage of wheat, up to 10 percent, and possibly some light Munich or Vienna to add some depth,” Dutton says.
He adds that Track used to include some caramel malt to build body, but like many American breweries, they have moved away from that. Instead, they compensate in the mash. “We aim for a high mash temp, around 162°F [72°C]. This helps get some body in the beer and packs a bit more malt flavor in there, while also giving the hops something to hang off.”
While these beers have morphed with modern hopping, other ingredients are critical in maintaining that classic bitter character.
“Yeast is by far the most important ingredient in bitter,” says Paul Jones, cofounder of the Manchester-based brewery Cloudwater. After all, house yeasts are what made those legacy bitters distinctive. “It’s what makes someone a fan of J.W. Lees, but not so much of Holt’s, or a fan of Holt’s but not so much Harvey’s.”
American brewers have learned how valuable English yeast strains can be in their IPAs—London III, for example—by contributing fruity esters and sometimes boosting hops via biotransformation. British brewers have valued them for centuries.
Each brewery I asked said they use a different strain from the others. All emphasize how important it is to their own beer’s profile.
Yes, These Are Bitters
Because bitters have been so stable for so long, one can reasonably ask whether these qualify as the same style. Indeed, many breweries reserve the word “bitter” for the more traditional formulation, calling the modern style “pale ale” or something else—and maybe they sell better that way.
Historically, however, stability was not a hallmark of British bitter. At the end of the 19th century, it was stronger—5.5 percent ABV or more. It was also truly bitter, with hopping schedules that suggest they’d often exceed 50 IBUs. They even routinely used American hops—though they weren’t highly regarded and were mainly used for bittering.
Even if the world wars ultimately sent the gravities plummeting, brewers continued to produce them at different strengths. Regional differences persist, as does variation in ingredients and serving style. British drinkers still debate the use of “sparklers,” which create a mousse-like head on a pint of cask bitter. It’s a more dynamic tradition than it appears, which makes modern, hop-forward bitter look more like the latest chapter in its story.
Ultimately, however, the proof for me is in the pint. Cask bitters are a master class in balance. The ingredients all rely on each other; the silkiness of natural carbonation balances the low ABV; the fullness of the malt balances the crisp, lean finish. In this modern version of cask bitter, those elements remain in place. The hops pick up the yeast’s esters in the nose, and they complement the soft, bready malts with a citrusy tang. Modern hops make cask bitters brighter and zippier, as if charged with a small electrical current—but they remain eminently easy to drink, pint after pint.
The Brits are the ones who invented the term “sessionable,” after all, and that quality is what continues to define modern cask bitters.
As American brewers mine the world for fresh ideas, it’s well worth taking another glance at Britain—and then catching a plane. What’s happening there is remarkable and ripe for rediscovery.