On Saturday, July 20, Colorado’s first and oldest craft brewery, Boulder Beer Co., celebrated 40 years in brewing with special tappings, live music, karaoke, and a rare vertical tasting of Boulder Beer’s Killer Penguin Barleywine Ale.

Originally founded in 1979 by two University of Colorado Boulder astrophysicists — David Hummer and Randolph “Stick” Ware — and engineer Alvin Nelson, the Boulder Brewing Company began humbly on a goat shed roughly 15 miles north of Boulder.

The hobby turned dare turned business started when Ware, a homebrewer from California, suggested that he and Hummer, a homebrewer who had developed a taste for English ales while studying at University College, start their own brewery — the first craft brewery in the state. Five years later, they relocated from the goat shed to Boulder and built their facility on Wilderness Place. They’ve been there ever since.

The story of Boulder Beer is heaped with history, which is why it seemed appropriate that Killer Penguin should be the beer to commemorate the occasion. As host and brewmaster David Zuckerman — who has been with the brewery since 1990 — explained, barleywine was once a style favored by British pensioners living on a fixed income who chose the beer for its high alcohol content (6–12% ABV) and low cost. The market followed suit, making barleywine cheaply and economically, reducing the style to something resembling malt liquor here in the states.

Enter the American craft brewer. Lacking tradition and a national style — beyond mass-market lagers — many gravitated to the flavor and tradition of English ales. And though barleywines were never as prevalent as bitter, brown, India pale ale, or stout, the big, malty ale has held a special place at many breweries, particularly during the winter months.

Zuckerman can’t recall when they first started brewing Killer Penguin at Boulder Beer — he estimates the first iteration was in the mid-90s — but the recipe has remained virtually unchanged since. Brewed with pale and crystal malts, hopped with Willamette, Cascade, and Nugget, and fermented with a neutral English ale yeast strain, Killer Penguin is the perfect beer for a vertical tasting as it highlights how age affects a beer, not how a recipe evolves.

And KP’s base was evident primarily in the color of the beers poured — vintages 2005, 2007, 2009, 2010, 2015, and 2018. Other indicators were carbonation levels and hop presence. Being only a year old, the 2018 KP showed fresh and tightly wound hops. The caramel malts came through in the end, but the beer lacked the maturity of even the 2015 KP, which showed a decent amount of carbonation, floral hops, and nary a hint of astringency. The beer was full in the mouth, sweet and smooth with complex flavors of caramel, maple syrup, and brown sugar.

As a contrast, the 2005 vintage featured no carbonation and little-to-no detectable hops. Instead, the brew had matured and deepened into a soft aroma of golden raisins, prunes, and a touch of candied almonds. The flavor was somewhat nutty, with touches of cedar, dark fruit, and a bit of sugar in the raw.

From left to right: 2018, 2015, 2010, 2009, 2007, 2005.

The 2005 KP displayed in malt what the 2015 KP conveyed with hops. Both beers tasted surprisingly similar while also showing their age. Vintages ’15 and ’05 were the clear favorites, overshadowing the beers in between while exemplifying the progress a beer takes in the bottle while showing depth and complexity. These barleywines were a far cry from the treacly brews British pensioners once quaffed.

“One of the great things the American craft brewing industry has done, is taken a style like this and elevated it back to what it really was,” Zuckerman told the tasting room. “It’s a great example of the industry raising some of the beer standards.”

It’s also an example of how the industry has changed. Zuckerman isn’t anticipating brewing a 2019 Killer Penguin. The name is too well known, and the style isn’t hip anymore. Hazies, pastry stouts, and sours are currently en vogue, as are new breweries, new beers, and new names. They could change the name and the recipe, Zuckerman supposes, but the chances of a barleywine taking off in the 2019/2020 marketplace is doubtful.

How poetic that Colorado’s oldest craft brewery would celebrate its anniversary with a tasting of a style that may soon be relegated, once again, to the history books. Maybe even forgotten. But, if breweries like Boulder Beer are any indication, the history is never gone. It’s just waiting to be discovered again.

Brewmaster David Zuckerman and marketing director Tess McFadden host Boulder Beer’s Killer Penguin tasting.