The story behind GUINNESS Blonde American Lager

Hear the folks at Guinness describe the heavily guarded St. James’s Gate facility where the brewer stores the master culture of its yeast, and they’ll sound as if they’re talking about some secret lab where government scientists have preserved the body of an ancient alien life form. Few visitors will ever witness a fully sanitized tech pulling the prized microbes out of a chamber smoking with liquid nitrogen -- though those who do will admit that, despite being over 125 years old, the strain looks a lot like, well, yeast. Still, the stuff is sacred, so it’s surprising that when Guinness’s brewers decided that their ale yeast would be used in an American lager -- Guinness Blonde American Lager, to be exact -- the internal reaction wasn’t cries of sacrilege.

"There was a sense of excitement,” says Michael Donnelly, Guinness Master Brewer and head of product development. “It was perceived as a challenge.” What was more surprising was that, after 31 years with the company, a man like the Dublin-born-and-bred Donnelly would feel confident handing over a significant amount of responsibility for the unprecedented project to a guy from Pennsylvania.

Of course, Joe Gruss wasn’t just any Pennsylvanian. His father was a brewmaster at Latrobe. He got his own start sweeping that facility’s floors in college, and has now been in the business 35 years, putting in time with Schlitz before coming back to work with his dad and eventually becoming a Latrobe brewmaster himself.

Guinness had already decided that everything in Guinness Blonde would sourced from America -- the hops, the malts, and the location of its brewery. The yeast and centuries-old know-how would be the Irish contribution. They’d landed on a lager because, despite the craft beer revolution’s championing of IPAs, the lager is still by far America’s most popular style. Having rolled out Rolling Rock in 1939, Latrobe knew lagers well; and, Guinness was also impressed with the facility’s track record of contract brewing.
 
“They saw how we treated the liquid and said, ‘We think you can do this,’” says Gruss. “They have  over 250 years of brewing experience -- it’s a lot to live up to. Guinness had more confidence than we did.”

The goal wasn’t simply to produce a generic lager, though. Instead, Guinness wanted something new: a beer that catered to traditional American tastes, but that did give a healthy nod to the craft beer movement’s love of hops -- and managed to retain the Guinness identity. In spirit and chemistry this was a far different effort than previous American releases (Guinness Gold in 1988; Black Lager in 2011), most crucially it would include the imported yeast from St. James’s Gate, rarely used outside of Dublin. 

Yeast microbes are like people: they act completely differently on vacation. Simply bringing the yeast to the Mid Atlantic meant certain changes could be expected in its fermentation process. Asking it to behave like a lager yeast (ale yeast is top-fermenting, lager bottom-fermenting) meant even more trial and error.
 
The first attempt -- fermented at 15 degrees C, the highest temperature lager yeast is typically subjected to -- tasted like the batch had gone bad in travel. After transatlantic consultation with Donnelly, Gruss raised the temperature to 18 degrees, well within ale yeast’s comfort zone but a bit above lager’s. No one’s sure exactly why, but the gambit worked; once they realized they weren’t vacationers but expats forming a distinct community abroad, the yeast microbes acclimated.

Right off the bat, Crystal Malt complemented the butterscotch-tinged esters in the yeast, making things nuttier and more caramel-y. The bigger challenge came with the hops. Nowhere in the world is as hop-mad as America right now, and while Western European brewers respect -- and maybe sometimes envy -- the U.S.’s bold experiments with bitterness, they also feel that over-hopping can serve to mask mistakes.
 
For Guinness Blonde, Guinness wanted the bitterness to be less overwhelming. Not because they were seeking to create some sort of introductory beer, but because when you’re hybridizing two brewing traditions and a revolution, balance is everything.
 
At first go, the brewers went with just Willamette and Mosaic hops, the former for its aromatic qualities, and the latter for its clean, complex bitterness. When both taste and analytical tests indicated the brew was still too bitter, they added Mt. Hood hops, which managed to bring more spiciness while softening the overall product. Thinking they had a winner, the Latrobe brewers shipped the beer Dublin’s way. Dublin enthusiastically agreed.

Guinness is legendary for its addiction to quality and consistency. One of its chemists invented the famous (in scientific circles) “Student’s T-Test” in 1908 as a means to ensure excellence amongst every batch of stout. The company spent decades perfecting the widget that enables perfect pub pours from bottles and cans. And its devotees are obsessive about the two-pour system and perfect pouring temperatures.
 
In this respect Guinness Blonde has it easy, because even a complex lager is far less particular than a stout. Brand director Doug Campbell -- who like many American employees “bleeds black” for the brewery -- cautions that over-chilling will rob you of catching the esters off the nose. But beyond that, he says there is no complicated serving process. “As long as you hit your mouth, you’re probably okay.”

As for the beer’s future, both Campbell and Gruss say the reaction so far in America has been strong among both stout fans and lager lovers. Though it’s still early, there’s even a bit of demand back in Europe, some coming from Donnelly’s own team: “We already shipped a little back here… just for quality control purposes of course.”

If that trend develops, it could ironically lead to America exporting Guinness to Ireland. Once you unleash that yeast, anything can happen.