At Bernardo Winery, 50 large redwood vats have resided in the warehouse for more than a century. Until the 1960s they were used as fermenters, but today winemaker Ross Rizzo keeps the vats as decor to charm the guests. They are, after all, useless, hopelessly infested with Brettanomyces, a notorious genus of yeast that strips wines of their fruity esters, leaves an incorrigible scent of barnyard, and can wreak havoc and financial wreckage on a winery if allowed to thrive uncontrolled. Winemakers have battled with this bug for centuries.
But beer makers are learning to love it. Worldwide, and throughout San Diego County, brewers are intentionally infecting their beers — mostly Belgian-style, barrel-aged beers — with Brettanomyces, as sour ales, an unlikely favorite, catch on among the beer-drinking elite. Greg Koch, founder of Stone Brewing Co. in Escondido, hosted the third annual Stone Sour Fest on July 19. More than 600 guests attended to taste the 90 beers, some as tart as lemonade and most bearing scents of horse, hay, alfalfa, and a general barnyard funk.
Koch first encountered sour beers during a 1995 beer-tasting tour in Belgium, where brewers have traditionally left fermenting beer exposed to the elements in a method called “spontaneous fermentation.” Brettanomyces and several other “spoiling agents,” as winemakers call them, literally blow on the wind throughout much of the world, and ales exposed to these microbes and aged for months or years in barrels slowly attain sourness and a funky complexity. Acetobacter — the creature that makes vinegar — Lactobacillus, and Pediococcus contribute to the overall acidity and pungency of the style.
Although Koch loves well-made eye-watering ales, he chooses not to use Brettanomyces in his own facility.
“If you’re not careful, these bugs can get into every nook and cranny and infect all your equipment,” he says.
Wineries face the same risk. In 2005 at Orfila Vineyards in Escondido, 120 oak barrels were discovered to contain Brettanomyces and had to be scrapped — sold to a hardware chain for use as garden planters, according to the current winemaker, Don Reha. The affected wine was not yet ruined and bore only the faintest scent of Brettanomyces, but it was sold onto the bulk market anyway. Reha says that French wines often contain souring microbes. The average consumer, he says, won’t notice just a trace, but a heavy concentration must be dealt with, either by blending it away or running the wine through a specialized 0.25-micron filter.
Rizzo observes that wine, unlike beer, absorbs the effects of Brettanomyces and its cousins in a usually unfavorable way.
“Wine is much more susceptible to some of these pathogens and bacteria and can easily be turned into a horrible-tasting liquid,” he explains. “In beer, these bugs tend to make them ‘interesting.’ ”
But just a trace won’t hurt a wine, says Rizzo. Twenty percent of his own wine, in fact, is made in the same room as the winery’s infected redwood vats, and Rizzo says these wines contain limited amounts of Brettanomyces, which impart a pleasant toasted-oak flavor. If allowed to thrive, however, the mild effects could escalate to the “barnyard” level — and eventually “dirty diaper.” Beer, too, can be overwhelmed by the essence of Brettanomyces. Colby Chandler, brewer at Ballast Point Brewing Company in Linda Vista, describes such afflicted beers as smelling like goat, and, clearly, brewers who cultivate Brettanomyces in their barrels and bottles are walking a narrow line.
Brettanomyces was first isolated and named in Denmark in 1904 by N. Hjelte Claussen, then director of New Carlsberg Brewery. This was the post-Pasteur era, when the understanding of microbes, “germs,” and general sanitization was advancing rapidly. Other yeasts had been isolated too, including Saccharomyces, which became the favorite of beer makers. Putting their new understanding of microbiology to work, brewers gained heightened control over their product by keeping unwanted organisms out of fermenting vats, barrels, and bottles. Brettanomyces, which easily infects wood and can remain dormant in barrels for years, was identified as a leading cause of sour beer and wine, and it became something feared, hated, and suppressed. Only at select breweries in Belgium and Germany would sourness remain a desired attribute, and for roughly a century, Brettanomyces was blacklisted. Then, just about a decade ago, brewers gave it a second chance, and now Brett, as brewers affectionately call it, is a rising star.
White Labs, Inc., in San Diego cultivates more than 50 strains and species of yeasts and bacteria for commercial and home use in brewing and winemaking, including three strains of Brettanomyces and a “sour mix.” Neva Parker, the lab’s manager, says she has seen the increased demand among brewers for White Labs’ souring agents. Parker says that, though beer can gain “complexity” through the tactful use of Brett, the fruity esters of wine tend to decay and vanish in its presence. The yeast works very slowly, however; whereas Saccharomyces can fully ferment a batch of beer in just several days, Brettanomyces requires at least six weeks to affect a beer’s flavor and turn the sugars into alcohol. Brewer-owner Pat McIlhenney at Alpine Beer Company feels that at least three months is required to make a sour beer, but Tomme Arthur, director of brewery operations at the Lost Abbey in San Marcos, says that good Brett beers require even longer.
“You can’t make a good one in less than six months, and you can’t make a great sour beer in less than a year,” he says.
To Chandler at Ballast Point, who has several barrels of sour fruit beers currently maturing in the cellar, making these beers requires a brewer to think like a winemaker.
“They take up space, and you have to think years ahead in terms of production, where to keep them, when they’re ready, and then what to do with them,” he says.
In turn, prices can be high. Lost Abbey’s sour ales begin at $15 for a 375-milliliter bottle and top out at $30 for a 750-milliliter bottle. Still, the beers are selling. When he founded the Lost Abbey in 2006, Arthur made 8 barrels of sour beer. This year he has made 200, and production is on the rise — as is demand for infected barrels. At Bernardo Winery, Rizzo has turned away brewers asking to have his redwood vats, preferring to keep the artifacts as decor. And at Orfila Vineyards, winemaker Reha plans to keep Brettanomyces and its funky cohorts out of his winery, but should a problem arise and the critters turn up, he will likely sell any infected barrels into the sour-beer business.