Hoppy beer has become extremely popular with the rise of craft breweries. Today, the hoppiest beers — largely IPAs, characterized by their bitter flavor — can be found in any brewpub, flaunting their high alcohol content and extreme bitterness. Hops, however, are unwieldy and expensive, which is why researchers at the University of California, Berkeley, have developed a new method for brewing hoppy beer that doesn’t require any hops.
Hops are a water-intensive crop, so making hoppy beer can exact a significant financial toll. And because their essential oil content, which imparts their unique flavor, is so variable, it’s difficult to brew hop-filled beer consistently. Good thing, then, that the alternate brewing method detailed in the new Nature Communications study on Tuesday doesn’t need hops at all. “My hope is that if we can use the technology to make great beer that is produced with a more sustainable process, people will embrace that,” lead author Charles Denby, Ph.D. said in a statement.
The researchers cut out the hops by replacing them with genetically modified yeast designed to pump out monoterpenes — the molecules that give hops their distinctive flavor. With Cas9 gene-editing technology, the boozy biologists spliced together a unique strain of brewer’s yeast, which they then used to make the beer. The gene editing technique works by using short strings of genetic code to target and remove specific portions of DNA with the Cas9 enzyme, which acts like a pair of scissors. In the gap, scientists can insert different DNA from pretty much any other organism.
In this case, the researchers added a DNA cocktail made from the genes of mint, basil, and other yeasts — in particular, the genes associated with monoterpene production. The beer brewed with this genetically modiifed yeast was then subjected to a taste test, judged by a panel of trained tasters from the Lagunitas brewery. In the double-blind taste test, the hop-less beer was actually perceived as hoppier than the traditional hop-filled brews.
Given the results of the experiment, it’s possible that smaller breweries without the resources to invest in hops could switch to hop-flavored brewer’s yeast once it becomes widely available. Denby plans to market the yeast through his startup, Berkeley Brewing Science.
Despite the contentious debate surrounding GMO foods, the creation of tasty, hop-free booze seems like one application of gene editing that everyone can get behind. So kick back, crack a beer, and propose a toast to science.