Future beer

Will new yeast take strain off hops production?

As much as some foodies like to bash truffle oil, the stuff comes respectably close to mimicking the real thing. It is made using a compound that occurs naturally in those fragrant fungi but that can also be synthesized in labs.

We should not be surprised, then, that a similar sort of alchemy is now being applied on behalf of beer’s best-known ingredient, the hop. A team of scientists from UC Berkeley has created a yeast strain that consistently produces the fruity, grapefruit-like flavors of the mighty Cascade hop, the most popular variety of the fragrant blossom in the country.

This is potentially groundbreaking work, as it could mean brewers can make the kinds of beers consumers want but without having to buy expensive, resource-intensive hops from farmers in the Pacific Northwest.

But there’s a catch, and it’s likely to rub millions of consumers and brewers the wrong way: The novel yeast has been genetically modified. Craft beer has remained a sector of the food economy almost entirely untouched by genetically modified organisms, or GMOs. While the yeast remains isolated to the lab where it was born, the lead researcher on the project, biochemist Charles Denby—also an avid homebrewer—hopes to take his yeast to a commercial scale.

His intentions are good.

“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,” he said via email. “If anything, this adds to craft brewing. This is another tool brewers can use to make beer.”

He and his colleagues created the new yeast by splicing genes from mint and basil plants into the DNA of brewing yeast. The result of their work is a yeast that turns sugar into alcohol—yeast’s primary role in brewing—while also creating the same aromatic molecules that occur in the Cascade hop.

And not only does the yeast create aromas resembling those of the Cascade hop; the yeast does it remarkably well. Test batches of beer made using the yeast were served to a panel of tasters assembled at Lagunitas Brewing Co., in Petaluma. The trained participants perceived the experimental beer—made without the late-brew addition of flavoring hops—to be hoppier than a traditionally hopped beer, according to the scientists, who published their research in March in the journal Nature Communications.

Already, brewers are balking at the development. Matt Brynildson, brewer at Firestone-Walker Brewing Co. in Paso Robles is concerned this could lead to a brewing industry that has abandoned hops. Brynildson says he particularly enjoys the nuanced work of creating aromatically balanced hop blends in his beers.

“The purist brewer in me says, ‘Why would you want to take the most exciting part of making beer away from me?’” he said.

Creating new yeast strains is an old practice. However, it has traditionally been done by isolating desired strains through selection. Some yeast strains have been in use for centuries.

At White Labs in San Diego—one of the main suppliers of yeast for the beer industry—senior research scientist Karen Fortmann said her lab specializes in preserving popular yeast strains by freezing them and, through careful monitoring, preventing genetic drift. That way, ancient yeasts can be maintained as they always were.

Fortmann said she finds the new research interesting, although her company isn’t planning to dabble in genetic engineering, mainly because customers—both beer drinkers and brewers—tend to be uneasy about the idea. Fortmann said she understands this knee-jerk reaction to GMOs.

“I get the whole robots-are-taking-over-the-world fear” of the world and its artforms becoming automated or synthesized, “but even if you had genetically modified yeast creating your aromas, there’s still quite a lot of artistry that goes into brewing,” she said.

At Drake’s Brewing Co., brewmaster John Gillooly believes the yeast strain produced by Denby’s lab could truly help solve problems.

“Growing hops is tough on the planet, and as responsible stewards of the land we should be trying to take some of the agricultural load off of the Yakima Valley,” he said, referring to Washington’s famed hop-growing region. If a genetically modified yeast allows brewers to make hoppy beers using less of a resource-intensive crop, then he says he is all for it.