Mmm, Beer: Brewers Are on a Quest to Breed a Better Hop
http://www.wired.com/2015/08/mmm-bee...eed-better-hop

FOR CRAFT BREWERIES, originality is everything. Your favorite microbrew prides itself on the particular combination of grains, yeast, and hops that go into its fermented nectar. Regardless of the magic that goes into the recipe, though, a lot of those ingredients come from the same big suppliers—bulk barley, high-yield yeast. So when agricultural geneticist Sean Myles was visiting his brewing buddies over at Tatamagouche Brewing Company in Nova Scotia, the conversation turned quickly to the one place where microbreweries can really distinguish themselves: hop varieties.

“I’m a craft beer fanatic…a little bit,” says Myles, who researches at Dalhousie University. “I ended up hanging around the hop yard, and we were taking a look at the vines.” In Nova Scotia, brewers grow the same varieties of hops you’d see elsewhere—Cascade, Willamette, Fuggle—which add aroma, flavor, and bitterness to a beer while helping to preserve it. But the vines don’t thrive like they do on the dryer, warmer west coast. The region’s high humidity makes the plants vulnerable to mildew. Myles looked at the hops growing in the brewers’ backyard, stunted and suffering from fungus, and had an idea: “I said, well, let’s go get some pollen.”

So Myles and Hans Christian Jost from Tatamagouche traveled from Nova Scotia to Corvallis, Oregon, where the USDA has one of the biggest hop collections in the world. “In order to get new varieties you need to let these plants have sex and generate some offspring,” says Myles. The National Clonal Germplasm Repository—which includes a gene bank in addition to physical collections of berries, mint, and nuts—is one of the only places where hopheads have access to pollen from male plants. (The pine cone-shaped hops that go into your beer are the flower of female plants, so most growers don’t bother keeping any males around.)

At the USDA hop library, which has dozens of varieties bred for different taste profiles, disease resistance, and viability in different climates, Myles worked with hop expert John Henning to find four different male mildew-resistant hops. But he couldn’t take the plant material across the border to Canada—so he stuck baggies over the top of the plants, collected their pollen, and brought it back to sprinkle on top of the female flowers grown by the brewery.

That’s the beginning of what will be a multiple-year process of growing, seed collection, and growing again to select the most mildew-resistant plants that still keep their floral hop character. When the brewers are done, they’ll have a unique variety of hops that they can call their own—and hopefully grow more of, thanks to its improved mildew protection.

The process that Myles is using isn’t just to help brewers in humid climes grow their own hops. Other breweries are using traditional breeding techniques to create hops with novel flavors and smells, created by each plant’s specific combination of volatile aromatic compounds. “The complexity is sort of infinite,” says Myles. “More people are researching the desirable and undesirable volatiles, and whether they’re heritable.”

What gives a fantastically floral hop its character is more difficult to nail down than resistance to a specific disease, though. While Myles and his team can be fairly confident that their cross-breeding will result in at least one good mildew-resistant hop, it’s tougher to reverse-engineer the genetic architecture of a super-citrusy aroma—whether it’s the result of many small genetic changes stacked on top of each other, or overwhelmingly determined by a few dominant genes.

Luckily, hopheads are open to experimentation—crossbreeding over and over again in the search for the perfect aroma and a high-performing vine. Other parts of the alcohol industry turn their noses up at cross-bred varieties: “Breeders are crossing the noble European grapes with North American wild grapes suitable to our conditions, but the wine snobs won’t drink them,” says Myles, whose primary research is into the genetic diversity of grapes and apples. The craft beer industry, on the other hand, doesn’t give a crap about ancestry. “Hopheads are embracing diversity,” says Myles. “Wine snobs are viticultural racists.”

By splicing and dicing the genetic diversity found in wild varieties of hops—one of the most popular hop varieties, Cascade, is a cross between a wild North American and a noble European—craft breweries will be able to capitalize on untasted flavors and unsmelled aromas. “It takes the local food movement to a new level,” says Myles: “Your own, indigenously bred variety of hops.”