Travels with Barley (19 page)

Once you find the cell you like, you pluck it out with a device called an inoculation loop, put it in starter, and off you go. The technical term for culturing up yeast like this is to clone-purify them.

Maribeth started homebrewing about thirteen years ago after meeting Steve, who had taken it up seven years earlier. (They married
in 1995 outside the Anchor Steam Brewery in San Francisco and brewed a stout from the emulsified remains of their chocolate wedding cake.) She began looking around the yeast landscape and found it rather bare. And most homebrewers were not yet that yeast-savvy and didn't appreciate the significant connection between the taste and character of their beers and the yeast they used. A few people did, and some of them were even starting to clone-purify. “But they acted like it was voodoo magic,” Maribeth said. “You had to have a glove box (a small clean chamber) and autoclave (essentially a pressure-cooker) and all this special equipment. I said, ‘No, we do this all the time in the lab without such things.'” Her lab skills told her that after ordinary sterilization techniques, like submerging vessels in boiling water, you could keep vials, test tubes, beakers, and the like sterile by simply draping them with a common household item: aluminum foil.

She began teaching her techniques and preaching her yeast gospel at homebrew club meetings and conventions, including her hometown club, the Maltose Falcons (which happens to be the oldest homebrew club in the nation). “You were trying to tell them yeast was making an impact,” she said. “I would brew from the same wort and pitch four or five different ale yeasts just to demonstrate that point. I had one yeast that made a beer that tasted just like Jack Daniel's. The yeast was the only explanation. I could show them that the Bass Ale yeast makes an ale that tastes like Bass.”

She dove into clone-purifying after a fellow homebrewer, who needed a lot of yeast for some 50- and 100-gallon batches of beer he planned to make, asked her to produce enough to do that from a tiny sample of a yeast strain he already had. (Though yeast is cheap to buy, it's still even cheaper to clone.) Word soon got around that MB, as her friends often call her, was seriously on to the yeast thing.

Traveling homebrewing friends started bringing back yeast samples from places as far away as England and Belgium, though with varying degrees of success. They would go into pubs, ask for some cask-conditioned ale, and, usually surreptitiously, pour a sample of it into a jar. (Imagine having to explain to airport security what you were doing with all those jars with beer dregs sloshing around in them.) Often, though, these friends visited breweries and got the samples simply by asking for them—a practice that most breweries have since wised up to and have mostly stopped. But the pub samples and gifts of yeast didn't always make it back in good shape.

“We had this friend who was going to Austria and he was going to visit all these breweries,” Maribeth said. “So I made up this yeast hunter's kit, just some small vials with stoppers on them and some pipettes. You could pop them open, pop in your beer sample or your yeast sample, and stick it in your shirt pocket, no hassles.”

The kit worked so well that two things happened. One: Maribeth started to accumulate a lot of yeast. “One guy alone brought back three separate strains of Pilsner Urquell [the Czech Pilsner that was the world's first golden, clear beer] and a bunch of Belgian strains,” she said. She would clone-purify the samples, test-brew with the clones, and, if they made good beer, store the samples in her lab nitrogen refrigerator for future use and propagation. Soon, she had so much yeast that she found herself with a small mail order yeast business. Second: the kit became so popular that she developed a cheap commercial version of both a capture kit and cultivating kit which she started selling through a third-party vendor. She only recently got out of the mail order yeast business to turn her attention to making a commercial success of Hollywood Blonde, but by then “I felt like I'd gotten rid of a lot of the misconceptions about how this all worked,” she said. And indeed, these days a number of online and corner store homebrew shops carry yeast capture kits starting at about $7.50. For about $300, including microscope, would-be yeast rustlers can outfit an entire yeast-culturing lab.

And just how common is it for people to actually invest in these things? “It's not at all unusual,” Bev Blackwood, a member of the Houston-based Foam Rangers homebrew club whom I'd gotten to know, told me when I queried him. “It's not for the casual brewer. You really need to be lab-oriented since you're talking agar plates, microscopes, stir plates, and the like. But several Houston-area homebrewers culture their own yeasts and I know of at least one who maintains his own private yeast bank on slants.”

Blackwood, in fact, said he had a yeast-rustling project of his own underway. He'd brewed a batch of beer that seemed to have picked up an infection in one of his bottling lines—meaning that some spoiler bacteria had intermingled with the yeast and given the beer a sour flavor. Blackwood turns out to be fond of a Belgian style of purposely made sour ale called gueuze (sometimes spelled geuze) that is originally fermented with wild yeast but which gets its predominant flavors from various microflora—i.e., bacteria—that Belgian brewers introduce into the fermentation cycle by exposing their fermenting beer to the open air. He had some bottles of gueuze at home so “what I did was to drink the gueuze and then save the crud at the bottom of the bottle, which is composed of the various microflora that have been working on the beer. I used this stuff to dose my new bottles. My theory was that if I was going to have to deal with an infection, it might as well be one that I'd enjoy drinking.” (The beer turned out swell.)

Maribeth, meanwhile, still undertakes special yeast projects: she'd just finished clone-purifying “on a large scale” some Chimay yeast for BJ's, a large brewpub chain that has an outlet near her. Chimay, a brand of bottle-conditioned Belgain ales brewed by Trappist monks, is one of the world's most beloved beers among the Beer Geeks; both American craft and homebrewers have gone wild for the style. Getting Chimay's yeast, however, isn't as easy as it used to be. “Ten years ago, when I was doing this,” Maribeth explained, “Chimay yeast in the bottle was
the
Chimay fermentation yeast. Then, they found out these wacky American homebrewers were cloning the yeast and making beer with it—and the American brewers were getting it. So, then they started using a special carbonation yeast for bottle conditioning. Now it's hard to get good Chimay yeast.”

So where did she get hers?

Maribeth smiled. “I can't give you all my secrets,” she said.

However, this much is known: both Wyeast and White Labs do in fact sell yeast that the Yeast People will tell you are the actual strains used by many big-name commercial breweries both here and abroad. For a variety of reasons they just can't be called that. For one, the yeast labs don't want to rile up the breweries; second, they don't want to imply that a homebrewer, having acquired a commercial beer yeast, will automatically be able to brew a beer that tastes exactly like the commercial beer in question.

It was this situation that provided my first inkling that beer yeast was the object of such passion, desire, and speculation. I'd introduced myself by e-mail to members of the Foam Rangers club, Blackwood among them, and was directed to their informative Web site. Browsing it, I was intrigued by an essay by Ranger Steve Moore, who had gone to the rather elaborate trouble of putting together a list of eighteen yeast strains sold by the commercial yeast purveyors and, drawing on the collective knowledge of the Yeast People, articulating whose yeast they actually were. One example was a yeast sold under the moniker “1056/American ale yeast” and nicknamed “Chico.”

“Everyone knows it's the Sierra Nevada yeast,” Moore wrote.

Another, called “Irish ale yeast,” was clearly the Guinness yeast, he stated. And then there was another dubbed “Pilsen lager yeast” from “a classic American Pilsner strain.”

“Yeah,” Moore wrote, “from the largest brewery company in America … and the world … somewhere around St. Louis. Throws a green apple/acetaldehyde flavor that is characteristic of Bud, if you aren't careful.”

When I later talked in person to Moore and Blackwood about this, they said that assiduously mining the yeast grapevine to try to figure out exactly whose commercial yeast was finding its way into the homebrew market was considered one of the great side sports in homebrewing. For the record, the Yeast People will say they could be wrong about such correlations. But when you talk to them in private, these things are considered to be so well known as to be beyond debate. Maribeth, when I asked her what yeast she used in her Dougweiser, said matter-of-factly, “That's the Rolling Rock yeast.”

Rolling Rock, of course, is one of the remaining surviving regional lagers, brewed by Latrobe Brewing Co. of Latrobe, Pennsylvania.

As to the theories of the availability of Bud yeast, the prevailing speculation is that it had long ago fallen into the hands of homebrewers, who traded it around under the moniker “Amateur Brewer's Yeast”—or “AB Yeast,” for short, the AB being a wink and a nudge that really meant Anheuser-Busch. It's a matter of historical fact that Anheuser-Busch was in the baker's yeast business until 1988; one of the Yeast People told me that for a while the baker's yeast strain it sold was actually the same as its Bud beer yeast strain. True or not, AB Yeast ended up in the yeast labs where it is sold under guises such as the one that Steve Moore described.

Beyond that, there are other ways the Bud yeast could have made its way into this quasi-public domain. Bud is pasteurized and filtered before bottling to kill any existing organisms, including yeast, so there's little chance that yeast could have been cloned directly from the beer itself. But given the tons of yeast that Anheuser-Busch uses annually and the number of people with access to it over the decades, it's hardly unimaginable that a thimbleful walked out of a brewery someplace one day and into the test tube of a yeast rustler. And, as we'll see, the possibilities don't end there. The official Anheuser-Busch position is that the yeast it uses today is from the original strain acquired by founder Adolphus Busch and is indeed proprietary. The company had no comment on whether people have or haven't cloned it.

It's hard to imagine that brewing had carried on for thousands of years, till the mid-nineteenth century, before it gained hard knowledge of yeast's role, but it did. Thanks to Antoni Leeuwenhoek, the Dutchman credited with inventing the first useful compound microscope in the late 1600s, scientists had long been able to see microorganisms, even yeast. But the prevailing wisdom had been that yeast and other microorganisms were the products of spontaneous generation; in the case of yeast, scientists believed yeast to be a by-product of alcohol, not alcohol a by-product of yeast. Thus, as noted earlier, it was left to Louis Pasteur, in his groundbreaking 1876 book
Studies on Beer
, to unwind and unlock the science of zymurgy—how yeast does the work of fermentation—and convincingly prove his statement that “fermentation is the consequence of life without air.”

Brewers (and modern-day yeast rustlers) also owe a huge debt to Emil Christian Hansen, a part-time novelist and full-time chemist at the Carlsberg Brewery in Copenhagen, who in 1883 first isolated a single cell of beer yeast and showed that yeast could be propagated and “banked.” Inspired by the work of Pasteur, Hansen had been asked by his superiors to tackle the question of why beer batches often spoiled in the summer. What he discovered was that beer yeast colonies of the time contained good and bad actors; the bad ones were cells that were dormant in the cool weather but sprung to life in the summer heat, throwing off flavors that spoiled beer. The good ones were what would become known as lager yeast—indeed,
Saccharomyces uvarum
is still sometimes known as
Saccharomyces carlsbergensis
in honor of Hansen's work. Until that moment, knowledge of yeast hadn't meant brewers were in full control of it. Hansen essentially “tamed” the beast and made possible the reliable replication of pure yeast strains (thus giving a huge boost to the unfolding lager revolution).

By one estimate, beer yeast is one of about 600 species of yeast in the world and they exist in every climate on earth. Most are harmless or, like
Saccharomyces
, beneficial, though some are linked to food spoilage. A few, like
Candida albicans
, the strain responsible for common yeast infections in humans, can cause minor health problems (and major ones in people with seriously depressed immune systems).