All About Beer Magazine - Volume 33, Issue 2
May 1, 2012 By

For nearly 40 years, beer drinkers in post-World War II America were conditioned to think the best beer was a bright golden color—clean and crisp without a hint of haziness, even at palate-numbing temperatures. A well-made beer was transparent and devoid of any sediment.

There were reasons, both cultural and commercial, that this was the case in post-Prohibition America: Families with German roots controlled most of the rapidly growing domestic breweries in the 1940s and 1950s. The trend accelerated as industry consolidation took hold during the 1960s. Lager beers became omnipresent. In addition, as beer was shipped farther from its point of origin and spent more time in wholesaler warehouses, filtering became important to stabilize the product and extend shelf life.

By the second half of the 20th century, pilsner-style lagers had won the beauty contest, thanks to the style’s thirst-inducing Champagnelike appearance.

Beers are filtered, using either cake or surface methods, and classified into three basic levels: rough, fine and sterile. Using cake or depth filtration,  beer passes through a powder substance, such as diatomaceous earth (fossilized marine alga diatoms), finings (isinglass, the swim bladders of fish) or perlite (volcanic glass). Surface filtration uses membranes to filter beer. With lautering, the grain bed acts as a rough filter. In lager beers, gravity helps the process, as the beer is dropped bright while aging. Some brewers also use a technique called cold filtering, where proteins clump together at lower temperatures and are easier to remove. While homebrewers filter beer at 5 microns to remove yeast, grains and hop sediment, commercial brewers typically go much further to as low as 0.5 microns.

As craft brewing expanded, some domestic brewers came to realize that filtration can go too far, stripping away the natural goodness of beer. Overfiltering can take out color, hop bitterness and proteins that add body and help form the beer’s head.

“I appreciate the extra mouthfeel and head retention of unfiltered beer,” says Andy Brown, the brewer at Wynkoop Brewing Co. in Denver, CO. Brown had been taught at brewing school that filtering was an integral part of brewing. Then he had an internship under Dick Cantwell at Elysian Brewing Co. in Washington state, where filtering was rarely used. After spending time at Left Hand Brewing Co., Brown came to Wynkoop, where beers such as the B3K Schwarzbier are unfiltered hits.

“B3K uses no finings at all. It’s aged 3 to 4 weeks in lager tanks, and the beer settles out. We then transfer the beer to a second tank for serving,” Brown says. The beer is one of a select few to win a Great American Beer Festival medal in two different categories. In 2011, it won bronze in the kellerbier/zwickelbier category after having won the gold medal in 2008 in the German-style schwarzbier category.

“We decided to enter it as an unfiltered kellerbier because the notes from one of the judges said the beer had too much body for the schwarzbier category,” Brown says. “We ended up with two GABF medals in two different categories three years apart with the same beer.”

At Uncle Billy’s Brew & Cue in Austin, Texas, kellerbier Hell in Keller took GABF gold in 2009 and silver in 2008 for brewer Brian Peters.

“All the beers we make are unfiltered. We actually don’t own a filter,” Peters says.

While Peters agrees that certain beers such as lagers benefit from filtering because “it tightens up the flavors,” he believes that in some cases filtering does not have a huge impact on the final product.

“I think that sometimes people make a bigger deal out of it than it is, but it can strip some flavor,” Peters says. “With our ales, we use Fuller’s yeast, and that tends to settle quickly. So we really don’t see the need for filtering.”

Brooks Carretta, the head brewer at Birreria at Eataly in New York City’s Flatiron District, said his brewpub makes slow beer to be served with slow food. The rooftop brewery sits above Eataly, a restaurant, market and wine store modeled after Oscar Farinetti’s famed shop in Turin, Italy. The concept was brought to Manhattan by celebrity chefs Mario Batali, Joe Bastianich and Lidia Matticchio Bastianich. The brewery was started as a collaboration involving Italian craft brewers Teo Musso of Baladin and Lurisia, Leonardo di Vicenzo of Del Borgo and Sam Calagione of Dogfish Head in Delaware, with Carretta running the operation.

“All of the beers we brew at our rooftop brewery are cask conditioned and unfiltered,” Carretta says. “There’s really no need to filter the beer because we sell everything right at the brewpub.

“I’m pro-filtering with a production brewery where you are bottling the beer,” Carretta said. “But unfiltered beer is beer in its natural state. It’s true to what craft beer should be. It is an artisanal product.”

Birreria is building a reputation for itself with beers named after famous Italian women, such as the Gina (Lollobrigida) Thyme Pale Ale. The Wanda (Osiris) Chestnut Mild Ale is unique because it uses roasted chestnuts imported from Italy.

The decision to filter or not filter can be the personal preference of the brewer or dictated by style, such as hefeweizen. But with unfiltered beers on an upswing, one might just be your next beer.


Rick Lyke
Rick Lyke is a North Carolina beer writer and founder of the Pints for Prostates men’s health campaign.