Berliner Weisse

In recent years, there has been a particular fondness for brews with “extreme” qualities. Intense hoppiness, rugged roasted flavors, wild funkiness and alcoholic potency all fit this bill. Sour flavors have most recently become a desired affection. Berliner weisse features a reserved lactic sourness as its keynote, the supplementary fermentation resulting in an effervescent, bone-dry beer, placing them among the most refreshing beverages, beer or otherwise. Rare even in Berlin, the recent general delight in sour beers has put them on our collective radar. Daring American brewers are dabbling in Berliner weisse, nouveau German artisans are reinventing it, and traditional brewers of the style are holding firm.

They couldn’t be more different from the spicy and textured hefe-weissbiers of Bavaria. Instead, they emanate from the swath of Northern and Central Europe where top-fermentation and wild influence was preferred, home to the beery rascals of lambic, Flanders red and brown, Gose and witbier. As Berliner weisse is investigated by today’s brewers, it is becoming something of an interpretive beer, often more in line with its older roots, curiosity ripe for further exploration.

Brewing with wheat is as ancient as beer itself, and barley has failed to displace it entirely. Wheat cultivation was widespread in Europe by The Middle Ages, with many regional brewers using it for their indigenous beers. Many of those old “styles” became extinct, but many persevered, as demonstrated by the vast assortment of beers that still feature raw or malted wheat. Often these were, or are, influenced by wild yeast and bacteria. Some brewers wisely opted to leave well enough alone in this respect, while others were intent on purging their beer of mischievous bugs, by careful selection of inoculating slurry or fermentation conditions.

Berlin began its life as a brewing city in 1572 and 1642 as a wheat beer brewing city, making beers undoubtedly influenced by the ubiquitous and inescapable lactobacillus and brettanomyces organisms. Berlin, now en route to becoming the brewing Mecca that it would by the 19^th century, was ready to stylistically refine a distinctive homegrown beer. This begs the query, “What lead to the development of the style?”

Some implicate the Huguenots, Reformed French Protestants who came to Germany to escape Catholic hostility. While scurrying across Northern Europe, they encountered numerous regional brews, including those of France, Flanders, Brussels and the Rhineland. These regions have given us an assortment of top-fermented modern brews, some of which were heavily influenced by wild bugs and often contained wheat. A more precise theory points to Cord Broyhan, an accomplished brewer who honed his craft in Hamburg and Hannover. His eponymously named Broyhan style became the most widely distributed type in Northern Germany during the 16^th and 17^th centuries. Relatively pale and low gravity, the popular Broyhan found a home among the opportunistic brewers of Berlin, one of the most vibrant and cosmopolitan cities in Europe.

Berlin became the preeminent brewing city in Continental Europe by the 19^th century. Berliner brewers did exercise a bit of individuality with their indigenous brew, and a single brewery may have put out several versions, varying the hop levels, strength and grain ratios. It was common for brewers to make strong stock beer and dilute it with water to the inclination of the patron. It may have been the signature thread of tartness permeating the Berliner weisse style that set it apart from other German brews. As the template was developed, unusual and archaic procedures were followed in spite of the progressive brewing that enveloped most of Europe. Wort was often not boiled, though some decocted, and mash hopping was employed as a filtering aid and to fully extract the preservative qualities. Typically, between 2 and 5 lbs of wheat was mashed for every pound of barley. As brewers elsewhere were moving towards bottom-fermentation and single-strain fermentation, Berliner braumeisters stayed true to their style. It was simply another regional specialty that may have been more at home in Belgium. In fact, Berliner weisse was sometimes reenergized with a dose of young, rambunctious beer, much as gueuze is made by blending old and young lambic.

Beliner weisse suffered the same fate as many regional beers during the latter half of the 19^th century, muscled aside by the invasion of pale lagers. It withstood the storm long enough to find port in the rapidly developing disciplines of fermentation science and microbiology to maintain their identity. Berliner weisse was not spontaneously fermented, but inoculated instead by the brewer, and identifying the organisms and conditions responsible was paramount to properly perpetuating the style. Biochemist Max Delbrück, while working at the Institute for Brewing in Berlin between 1932 and 1937, isolated the potent souring bacterial strain crucial to the style. It was dubbed Lactobacillus delbrückii, a common contributor also to lambic, gueuze, Flemish sours and the new North American Wilds.

Berliner weisse has not seen quite the same revival that many other older beer types have of late, but is still in a happier place than a generation ago. There are now several brewers in Germany making Berliner weisse (three in Berlin), some of which are a bit outside the modern stylistic norm, and more like older versions. Most are brewed and fermented in traditional fashion, with parameters and methods collectively unique to the style; minimal wort heating, single digit IBUs, low original gravity, top- and lactobacillus-fermentation, warm and cold conditioning, extreme attenuation, krausening, bottle-conditioning and prolonged maturation (often in stainless steel vessels).

The proportion of malted wheat has dropped to 30 from 50 percent. Wort is boiled for a very short time or kept just below the boiling point. This serves to sanatize the wort while retaining protein components critical to nutrition and metabolism of essential lactobacillus. Conventional top-fermenting yeast is pitched with Lactobacillus delbrückii and fermented at standard temps. After the proper attenuation is achieved, wort is sent to conditioning tanks and kept either warm or cold, depending on the brewery, perhaps with a shot of krausen. The conditioning beer continues to attenuate under the influence of lactobacillus and also develop its sour sharpness. It is then krausened again and bottled, and never pasteurized, encouraging metamorphosis in the bottle. Attenuation can approach 100 percent, leaving it extremely dry, with an ABV of 2.7 to 3.5 percent. This otherwise delicate beer with a piercing and puckering edge is usually softened with fruit syrups (mit schuss) in its homeland. Either the herbal green woodruff (walmeister) or red raspberry (himbier) are the most common. Those who have had their palates jaded by other assertive sour brews may find Berliner weisse fine without the sweet softeners. Berliner weisse has the legal protection of appellation d’origine contrôllée, the same as kölsch has in Köln. On this side of the pond, there are a couple of very common ones, Dogfish Head Festina Pêche and The Bruery Hottenroth, as well as a fair number of one-offs and experimentals. As brewers learn to tame and employ the “savage” lactobacillus, we may see more of these in the future.

The style is ready for a reawakening, and even savvy reworking. A more pleasant, refreshing marriage of sour and sweet does not exist.