Something’s Brewing in the Lab: Beer Without Hops
Posted March 20, 2018 5:38 p.m. EDT
If Americans will eat a burger with no meat, will they drink a beer without hops?
Charles Denby, a biochemist at the University of California, Berkeley, might have made it an option. Denby works in a lab that focuses on creating sustainable fuel out of plant molecules called terpenes. But he is also “a very enthusiastic home brewer,” he said. When he learned that some terpenes could, in small doses, impart the taste of hops — the small, green flowers that give beer its bitter, citrusy flavor — he decided to perform a side experiment.
Denby and his colleagues infused brewer’s yeast with DNA from basil and mint, two plants that naturally produce the hop-flavored terpenes. The scientists were aiming to recreate the flavor of Cascade hops, which are most popular among craft brewers. They used the engineered yeast to brew a hops-free ale.
There were some misfires.
“The real challenge of the study was to produce strains that produce flavor molecules at the right concentrations without sacrificing other aspects of the brewing yeast performance,” Denby said.
Once they perfected the formula, the tasting began.
“To me, it tasted distinctively hoppy, and not unlike a beer hopped with Cascade,” Denby said.
Wanting a more objective analysis, the researchers asked Lagunitas Brewing Co. in California to help them convene a double-blind taste test involving 40 participants. When asked to compare the brew’s hoppiness relative to traditionally brewed beers, the participants placed it above most of the competition.
“We were really excited to see that some of our strains produced flavors that were hoppier than conventionally dry-hopped beers,” Denby said.
The findings, published Tuesday in Nature Communications, could contribute to a more sustainable future for beer production.
Hops, one of beer’s four essential ingredients (the others are water, yeast and barley), come in dozens of varieties. Each bestows its own unique flavor. But they are a resource-intensive crop, requiring large amounts of water and sunlight to grow. The irrigation of hops in the United States alone requires more than 260 million gallons of water a year.
This is a growing problem for breweries. Over the past two decades, as craft beer has boomed, Americans have developed a strong preference for hoppy brews like India pale ales, driving up demand for the crop. But farmers can’t keep up, and brewers are facing a hops shortage that some say is slowing the growth of the craft beer industry.
Denby’s process, which he is hoping to commercialize, is a long way from putting hops farmers out of business. Still, he said, the technique could also help brewers produce a more consistent product.
“Brewers we’ve spoken with say that ensuring consistency of hop flavor is a constant challenge” because potency can vary among farms and seasons, he said. “On the other hand, the conditions inside a fermentor can be easily controlled.”
Either way, he said, “we’re really excited to make the brewing process more sustainable.”