The Lambic Beers of Brussels

If there is a cradle of beer civilization, it is Belgium, a country that has given us beer styles that have come to inspire brewers and beer drinkers the world over. Like much of old-world Europe, beer styles have become synonymous with their places of origin—like the Flemish Red-Brown of West Flanders, the altbiers of Düsseldorf or the Irish Stouts of, well, Ireland. Historically, the associations were predicated upon tradition and locally abundant ingredients. But today, most beers, though they originated from a particular place, can be made anywhere.

Lambic beers, however, continue to be unique to their place of origin. They came about in Flemish Brabant, in an area called the Pajottenland. It’s a rural area southwest of Brussels between the Dender and Senne rivers. The tie that links lambic beers and the Senne is not the grain that grows in this valley, nor the ability of the Senne to transport the beers to market—it’s the local bacteria.

The name Brussels means “of the marsh” (derived from the word Bruocsella). When it was founded, the city and the surrounding area, including the Pajottenland, sat within an extensive marshland. The resultant moist, humid environment and the flora, including the bacteria that it produces, make it the only place in the world that can produce lambic. In 1997, the European Union granted the beer its “Traditionally Speciality Guaranteed” label status. There is some disagreement in the derivation of the name lambic, but one theory is that the town of Lembeek, 20 kilometers south of Brussels and home of the well-known traditional lambic producer Brouwerij Boon, may play a role in the beer’s name. (The dominant theory is that the name comes from the alembic, a still used in the production of the spirit jenever, a predecessor to gin, likely because the beer was considered to bear a resemblance to the spirits of the time.)

The unique production of lambic seeks to take advantage of the bacteria produced by the Senne River. At Brasserie Cantillon, just a few hundred meters from the Brussels-Midi rail station, where Anderlecht borders Molenbeek, the brewing of lambic goes back more than 100 years. Fourth-generation brew master Jean-Pierre Van Roy makes sure that the family tradition is followed. Cantillon’s commitment to keeping things as they have always been, along with the scarcity of Cantillon bottles once you leave the area around Brussels, makes it the darling of beer lovers and the flagship lambic producer in all of Belgium.

It’s in the attic that the secret of Cantillon and lambic itself come into view. The brewing done here is similar to most of what you know about beer brewing. The standard formula for a lambic is two-thirds malted barley and one-third untoasted wheat. Unlike a lot of American brewers, Cantillon doesn’t use any fresh hops—bitterness is not the end game. Upstairs though, in the koelschip (or cooling vessel), this fairly standard beer approaches legendary status.

As the finished wort arrives upstairs, it cools in a large, shallow copper tank. The louvered windows are opened and the cool winter air of Brussels and the Senne Valley comes in to make its magic. Brewing can only be done in winter, because the summertime bacteria in the air are too unpredictable and brewers risk spoilage. The yeast and bacteria come from outside, as well as from the building itself, including the timbers of the roof and the wood barrels. There’s bacteria everywhere and it’s what drives the flavor at Brasserie Cantillon. Local bacteria and yeast strains with ridiculous names, like Saccharomyces cerevisiae, Saccharomyces pastorianus and Brettanomyces bruxellensis end up in the wort as it cools, aiding in fermentation and imparting those incredibly unique funky characteristics of this sour Belgian classic.

“We don’t produce quality beers here at Cantillon, we produce only natural beers. Quality presumes some sort of formula, and the only formula here is what nature gives us,” I’m told by the surly tour guide in a Motorhead T-shirt. Cantillon hasn’t changed a thing since 1900. It’s still using the brewery’s original equipment. A filter that I saw in the museum at the Rodenbach Brewery is the only filter used at Cantillon. While the lambic craze has come and gone, and most recently come back, the folks at Cantillon have not wavered from tradition, and in so doing they’ve become legends of the beer world. To hear almost anyone tell it, the lambic style was almost killed off by the soft-drink craze that was launched by Coca-Cola.

When Cantillon was founded there were more than 300 lambic brewers throughout Brussels and the Senne Valley. Today there are only 12, and only Cantillon brews lambic in Brussels. Many of the lambics brewed today are a non-traditional sweetened beer. The general consensus is that the soft-drink craze had an international impact on people’s palates and those taste buds drove the overtly sour lambic market nearly into extinction.

After blending the beers that have been fermenting in barrels for anywhere between one and three years, and spending another year fermenting in the bottle, the result of lambic production is called geuze. The name, thought to be derived from geyser, gets at the frothy, natural carbonation that the beer now possesses. Most geuzes are bottled with both a cork and a bottle cap, so the “geyser” name seems appropriate. Traditional, unblended lambic, which Cantillon still produces in its Grand Cru Bruocsella 1900, is completely flat.

The sour-beer craze in America has certainly turned the spotlight onto lambic beers, along with the more conventional sour styles. The day I visited Cantillon it seemed like every assistant working with Van Roy had an American accent. Lambics remain expensive, driven by the time involved in the production. A geuze can take four years to come to market. Cantillon is nearly impossible to find in the States and when you do it can cost up to a Benjamin. If you’re looking for a lambic Stateside, neighboring Brouwerij Boon produces a range of widely available geuze and kriek, and the 375ml bottle can often be had under $10. Frank Boon leads a lambic preservation group and his beers are certainly faithful to the lambic tradition. In addition to geuze and kriek, Boon makes a beer called the Mariage Parfait, which is mostly three-year-old lambic, and the single-vat series with beer from a single foeder. Boon does the vat series to show that each vat has its own signature yeasts, giving the beer a unique flavor profile.

Brouwerij Boon Mariage Parfait Geuze. Once a year, the brewers blend the barrels of three-year-old Geuze at Brouwerij Boon, and the resulting beer is a hyper-fermented geuze. It has aromas of tart lemon, early-season green apple and an earthy funk. The palate is lively, tart and complex. The green apple and citrus permeate but there is a funky undertone throughout. $10 (375ml)

Brouwerij Boon Kriek. Contrasted with an oude kriek, this Boon Kriek is loaded up with fresh Galician cherries, and while there’s a sense of tartness, it’s balanced with a sweet cherry aroma. This beer tastes just like it smells: fresh cherry, with a hint of nuttiness. While this beer is made from traditionally blended lambic, the fresh cherries comprise 25 percent of the beer, and they tend to dominate and add a touch of sweetness. The low alcohol percentage and fruity freshness make this a fantastic summer beer. $8 (375 ml)

Brouwerij Boon Oude Geuze. Per the regulations, an “oude” geuze must be a blend of one-, two- and three-year-old lambics; and that is the composition of the Boon Oude Geuze. The beer is hazy-golden hued and has aromas of wildflowers, tart apple and a funky brettanomyces scent. The mouthfeel is akin to Champagne, with a tart funky flavor that is signature to lambic beers. $10 (375ml)

From issue 75. Buy it here.