This GMO Yeast Can Apparently Create "Hops Flavored" Beer Without Using Hops

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This might be a time to invoke the old Jurassic Park adage of “Your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should!”

That’s not the kind of thing one says too often, within the world of craft brewing, but it might be valid right now: A team of chemists and geneticists in California has apparently created a genetically modified yeast, which they claim can impart the flavors of hop-forward beer styles into a brew without actually using any hops in the recipe. Or in other words, it’s a GMO yeast that claims to be able to produce beer that is vaguely IPA-like, without a single hop pellet making its way into the boil kettle.

In a long, occasionally creepy story in NPR, biochemist/homebrewer Charles Denby of the University of California discusses how the new yeast was created, by splicing DNA from mint and basil plants into the DNA of brewer’s yeast. This modified yeast then produces new compounds during fermentation—in this case, “the engineered strain consistently created the grapefruit-like flavors typical of the Cascade hop,” which is obviously one of the signature hop flavors in American brewing, made iconic by the likes of Sierra Nevada Pale Ale. And apparently, the hop notes are pretty convincing—the beer even “tasted hoppier” than control beers used in blind tastings performed at Lagunitas Brewing Co. in Petaluma, CA.

“Our goal is to help brewers create beers that achieve similar flavors and profiles as you can get from conventionally grown hops while reducing the environmental impact of brewing beer,” Denby said to NPR. “If anything, this adds to craft brewing. This is another tool brewers can use to make beer.”

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The potential cost-saving benefits for breweries are obvious, as sought-after hop varietals make up much of the ingredient cost in popular styles such as IPA. Equally obvious are an array of questions. Can these yeast strains be engineered to replace specific hop varietals? How about complex hops such as Mosaic, El Dorado or Galaxy, which tend to present differently in certain beers? Moreover, can you only make the equivalent of a “single-hopped” beer by using these yeasts, or can you combine them for a combined artificial hop profile? What happens when you add additional, real hops into a recipe that’s already using a GMO yeast that approximates hop flavors? I could go all day here.

Brewers, naturally, are immediately split in their reactions. Among the concerned voices is Firestone Walker’s resident “Merlin,” brewmaster Matt Brynildson. In his statements to NPR, it’s clear that the mere idea of GMO hops freaks him out.

“Craft brewing has always been a GMO-free art form — it was just assumed that we would never cross that line,” says Brynildson. “If we allow in GMO yeast, well, I could think of a hundred more things that I do or don’t want my yeast to do. If someone said they had a yeast that made wine flavors, and then winemakers didn’t have to use grapes anymore, that would be absurd. The next thing you know, we might be making beer with water, a drum of the cheapest sugar source you can find, and yeast that makes all the flavors that we used to get from barley and hops. That just wouldn’t be fun anymore.”

Likewise, even Sam Calagione of Dogfish Head, who has spent his whole career making innovative—and sometimes gimmick-laden—beers, seems to think this might be a bridge too far. To NPR, he said the following: “What does it mean for brewing if you can just buy the science to make whatever you want? I’m all for innovation, but we’re going to tread very slowly in this direction.”

Naturally, though, with more than 6,000 breweries in the U.S. in 2018, there are owners and brewers out there excited to try out the possibilities of GMO yeast strains. John Gillooly, the brewmaster of Drake’s Brewing Co. in San Leandro, CA, is also interviewed in the same story, and articulated his plans to use the yeast in an IPA that would be clearly labeled as originated from GMO yeast.

“I don’t see this ever replacing hops,” he said. “My sense is we’ll be coloring in with the hop flowers.”

And that’s without even getting into the stigma that GMO products possess among some consumers. With all these aspects included, it seems clear that GMO, hop-replacing yeast strains would probably face an uphill battle. But if they actually do prove cheaper to use than buying bushels of the latest sought-after hop varietal, you can be sure that some brewers will take the time to experiment.

This GMO Yeast Can Apparently Create “Hops Flavored” Beer Without Using Hops