Kölsch: The Delicate Beer of Cologne
In the world of beer styles, Kölsch is remarkable for being a formally defined style with a legally protected appellation within the European Union that limits its production to a specific geographic area. While this definition and recognition is relatively recent, the style has its roots in prior styles that evolved in response to competitive pressures to become the modern crystal-clear pale golden beer often described as “delicate” and “well balanced” with a “soft” finish.
But is this beer an ale or a lager? It’s both, actually, depending on how you define these terms. Germans typically define lagers as beers that have undergone a traditional cold maturation process, while characterizing beers as being either top-fermenting or bottom-fermenting based on the type of yeast used. Ales are considered a type of English beer rather than indicative of the yeast used. In England and the U.S., ales are thought of as top-fermenting beers and lagers are bottom-fermenting beers. But a Kölsch is a top-fermenting beer that has been lagered, much like the German altbier style. I once called these “hybrid beers,” but I think “lagered top-fermented beer” is more accurate and descriptive.
Beer writer Michael Jackson described the style as delicate and refreshing, and suggested that it makes a wonderful aperitif. In its hometown of Cologne (Köln, in German), the beer is served freshly poured from small casks in a tall, narrow, thin-walled 20-centiliter glass known as a stange (pictured to the left). The blue-aproned waiters, known as Köbes, keep them coming until you make them stop by placing your coaster on top of your glass, and track your order often by making tick marks on your coasters (kind of like a dim sum restaurant counting the plates). Yes, it’s as fun as it sounds.
Kölsch is style 5B in the Beer Judge Certification Program (BJCP) Style Guidelines, within the Pale Bitter
European Beer category along with the bottom-fermenting lagers leichtbier, helles exportbier (Dortmunder), and Pils. It tends to be not as bitter in the balance as the others in this group, while having a softer finish and a subtle fruitiness the others lack.
History
The city of Cologne has a long history from its founding as a Roman settlement in AD 50. Located on the western bank of the Rhine River in the state of North Rhine-Westphalia, it was an important city in the Holy Roman Empire and the Hanseatic League, eventually becoming the fourth most populous city in Germany. Cologne has a brewing tradition of more than a thousand years, including medieval times when it was brewing Keute (also known as Kuyt) and later gruit. In later industrial times, the beer of the area was known as Wiess (not to be confused with weiss, also known as hefeweizen). Wiess was a more strongly hopped, unfiltered pale beer made with up to 20% wheat.
Kölsch as we know it today emerged in the early 1900s as a clearer, more balanced version of wiess. The name Kölsch was first used to describe it in 1918, but the name basically means anything from Köln (kind of like how Pilsener means something from Pilsen). While being in a region with a strong top-fermenting tradition, the breweries resisted switching to bottom-fermentation but compromised by adapting the lagering process in response to the growing popularity of Pilsner-style beers. Bottom-fermentation was actually legally prohibited in Cologne, so perhaps the resistance was reinforced through legal protectionism.
Cologne was heavily bombed in World War II, with over 90% of the city being destroyed (thankfully, the landmark gothic cathedral was spared). Brewing was re-established and the style grew, but not as much as bottom-fermented beer did. This competitive pressure eventually caused the breweries to band together in a brewing association that attempted to protect the style. They developed a Kölsch Konvention — a document signed by over 20 breweries in Cologne and neighboring townships in 1986 — that defined the style and was eventually recognized by the European Union in 1997 as a protected geographic indication (basically, an appellation).
The protected appellation prevents others within the EU of using the name, although this does not extend to other places in the world. Some may choose to call their beer “Kölsch-style” while others may just call it a Kölsch (or Koelsch, the Anglicized spelling). The protection did not prevent some Köln breweries from closing or consolidating, but there are many still brewing and some bottle their product for export (notably, Reissdorf, Früh, and Gaffel).
Sensory Profile
Eric Warner’s Kölsch book gives a great sensory summary based on his first impressions of the style: “A light golden beer with a thick rocky head that is crystal clear, less malty than a helles, less bitter than a Pilsner, slightly fruitier than either, while being soft, well-balanced, and relatively light in body.” That is just as true today as it was when written in 1998. The Kölsch Konvention simply defines the style as a “light, highly attenuated, hop-accentuated, clear, top-fermenting vollbier.” Vollbier is a German tax class for beer indicating a product brewed from an 11–14 °Plato wort (OG 1.044–1.056) — in other words, a standard or normal beer (literally, it means “full beer”). Most examples actually top out at 12.5 °P (1.050).
Commercial Kölsch examples can have small variations in balance but they tend to be quite even between maltiness and bitterness. I don’t think they have any strong or sharp flavors, with the four major sensory components (maltiness, bitterness, hoppiness, fruitiness) varying in intensity from medium-low to medium-high, with none outright dominating. Commercial producers differentiate their products through small variations in balance, with some being drier, hoppier, and more bitter, while others seem more rounded and sweeter. Commercial versions are traditionally filtered to be crystal clear.
The beer is dry and well-attenuated but still retains a soft finish; it is not crisp, sharp, or biting like some Pilsners. Freshness matters in this style, and it can fade quickly with age. Oxidation can make the bitterness seem harsher, affect the softness and delicate flavor balance, and start bringing in papery flavors. I think it can seem somewhat like a slightly bitter cream ale or a subtle Bavarian Pilsner, if you are looking for comparisons.
The bitterness level is medium to medium-low, with a similar hoppiness that can have typical noble-type qualities (floral, spicy, herbal). The subtle fruity notes can sometimes be perceived as apple, pear, or cherry. The malt is usually Pilsner-like, with a grainy-sweet flavor sometimes with a hint of honey or bread. The flavors should be delicate and balanced, while allowing for some individual brewer variety.
The beer should be attenuated, not sweet, although the malt and fruitiness may give a slight impression of sweetness. The body is typically medium-light, although some can be as high as medium. Carbonation is moderate to moderately high. It should be smooth and soft, while dry, and never should seem heavy or filling. The alcohol range is typical for a vollbier, around 5% ABV or slightly less.
Brewing Ingredients and Methods
The ingredients for a Kölsch are fairly straightforward. It should be mostly pale or Pilsner malt, but can have a small amount of character grain (such as CaraHell®, Carapils®, Vienna, or wheat) to give a deeper color and add some flavor variety. Some sources (such as Warner and Kunze) mention grists of up to 15–20% wheat, but I have not seen this much used in practice. Very few breweries today use wheat (Malzmühle is one that does), and when they do, it is usually less than 5%. Perhaps the wheat level calls back to the earlier unfiltered wiess style, which often did have this amount.
Mashing regimes can vary, but most are step infused (Warner remarked that he was not aware of any Kölsch brewery not step mashing). Single decoction was sometimes used in the past, and a single infusion is viable, but step infusion tends to give the proper fermentability while retaining some body, and without excessive color development. The final gravity should be in the 2 °P (1.008) range, so be careful with methods (and grists) that go much higher. Conversion temperatures in the 143–146 °F (62–63 °C) are appropriate, followed by a rest at 156–159 °F (69–70 °C) and a mashout at 168–176 °F (76–80 °C).
Aroma hops should be traditional German noble hops such as Hallertauer or Tettnanger, but not too late in the boil (maybe with 10–20 minutes remaining). Bittering hops could be Perle, Magnum, or other German noble hops. Warner suggests a level of 16–34 IBUs, but I think most examples are in a narrower range. Personally, I think mid-20s works well. Water should be soft, with low alkalinity, avoiding excessive sulfates that could sharpen the finish.
Traditional Kölsch yeast is a powdery top-fermenting type that often is difficult to fully flocculate. This type of yeast lends itself to higher attenuation, but not so much to clarity unless other means are taken (mechanical or via finings). Common yeast strains are Wyeast 2565 (Kölsch), White Labs WLP029 (Kölsch Ale), or the SafAle K-97 dry ale yeast. Other suppliers sell Kölsch strains, and typically mention Kölsch or German Ale on the label. Confirm it by looking for a highly attenuative ale strain that produces a relatively clean flavor profile.
Fermentation temperatures are cool for ales, traditionally in the 55–59 °F (13–15 °C) range, sometimes higher (but usually not more than 68 °F/20 °C). The beer should be lagered after fermentation is complete, typically for at least a month at near-freezing temperatures. If lagering warmer, the duration will be longer (say, three months at 40 °F/5 °C). If the beer seems sulfury or vinous, it likely needs to be lagered longer.
Homebrew Example
My example shoots for the lower end of the style statistics as I think it is more refreshing that way. I think it’s important to have the right level of attenuation to keep the style from feeling heavy, so you have to keep the OG low as well or the ABV gets out of hand. As a dry beer, I don’t want to push too many IBUs at it, otherwise it will seem too bitter. To keep the finish soft, I’m also avoiding the higher IBUs, adding a touch of light crystal malt, and avoiding sulfates in the water.
My use of a step mash and lower mash conversion temperatures helps achieve the attenuation, but the fermentation and conditioning process also helps encourage the yeast to fully complete their job. I’m using mostly Pilsner malt for its flavor, with a touch of Vienna and CaraHell® to bump up the color, flavor, and body slightly.
My hop choice is a mix of German and American hops that mimic noble characteristics. Using all German noble hops is certainly appropriate, as long as you can source fresh samples. I’m using first wort hopping to keep the bitterness smooth and boost some of the hop flavor. The aroma addition is gentle.
A Kölsch-specific yeast should help with the attenuation and flavor, but don’t let the fermentation temperature rise dramatically. The subtle fruitiness should be natural, not forced through extreme temperatures. The lagering and conditioning phase is important for sulfur reduction and general smoothness – don’t ignore it. If you are shooting for a quick beer to make, maybe choose another style because actual lagering is part of what makes this style special.
Finally, remember that Kölsch should be brilliantly clear, so plan to either fine or filter the beer after it has lagered. I think this also tends to limit the shelf life of the beer, so you might want to drink it like they do in Cologne — fresh with the pints coming one after another. You may find that you have a new summertime house beer.
Kölsch by the Numbers:
OG: 1.044–1.050
FG: 1.007–1.011
SRM: 3.5–5
IBU: 18–30
ABV: 4.4–5.25%
Kölsch
(5 gallons/19 L,all-grain)
OG = 1.046 FG = 1.008
IBU = 20 SRM = 4 ABV = 5%
Ingredients
9 lbs. (4.1 kg) German Pilsner malt
4 oz. (454 g) Vienna malt
3 oz. (227 g) CaraHell® or crystal malt (10 °L)
1.4 AAU U.S. Liberty hops (first wort hop) (0.33 oz./9 g at 4.3% alpha acids)
4 AAU Hallertauer hops (30 min.) (1 oz./28 g at 4% alpha acids)
1.7 AAU U.S. Crystal hops (15 min.) (0.5 oz./14 g at 3.5% alpha acids)
White Labs WLP029 (Kölsch Ale), Wyeast 2565 (Kölsch), or SafAle K-97 yeast
3⁄4 cup corn sugar (if priming)
Step by Step
This recipe uses reverse osmosis (RO) water. Adjust all brewing water to a pH of 5.5 using phosphoric acid. Add 1 tsp. of calcium chloride to the mash. This recipe uses a step mash with a mashout. Use enough water to have a moderately thick mash (1.5 qts./lb.). Mash in all the grains at 131 °F (55 °C) for 10 minutes, then raise to 143 °F (62 °C) for 45 minutes, then to 158 °F (70 °C) for 15 minutes. Finally raise to 168 °F (76 °C) for 10 minutes to mashout, recirculating. Add the FWH hops to the kettle. Sparge with 168 °F (76 °C) water until 6.5 gallons (25 L) of wort is collected.
Boil the wort for 60 minutes, adding the hops at times indicated in the recipe. Chill to 58 °F (14 °C). Oxygenate, then pitch the yeast. After four days, allow fermentation temperature to rise to no more than 68 °F (20 °C) until fermentation is complete. Rack and lager for at least two months at or below 40 °F (4 °C).
Rack and allow the beer to drop bright, filtering or fining if necessary.
Rack the beer, prime and bottle condition, or keg and force carbonate.
Kölsch
(5 gallons/19 L, extract with grains)
OG = 1.046 FG = 1.008
IBU = 20 SRM = 4 ABV = 5%
Ingredients
5 lbs. (2.3 kg) light dried malt extract
3 oz. (227 g) CaraHell® or crystal malt (10 °L)
1.4 AAU U.S. Liberty hops (first wort hop) (0.33 oz./9 g at 4.3% alpha acids)
4 AAU Hallertauer hops (30 min.) (1 oz./28 g at 4% alpha acids)
1.7 AAU U.S. Crystal hops (15 min.) (0.5 oz./14 g at 3.5% alpha acids)
White Labs WLP029 (Kölsch Ale), Wyeast 2565 (Kölsch), or SafAle K-97 yeast
3⁄4 cup corn sugar (if priming)
Step by Step
Use 6.5 gallons (24.5 L) of water in the brew kettle; heat to 158 °F (70 °C). Steep the malt for 30 minutes, then remove.
Turn off the heat. Add the malt extract and stir thoroughly to dissolve completely. Add the first wort hops to the kettle. Turn the heat back on and bring to a boil.
Boil the wort for 60 minutes, adding the hops at times indicated in the recipe. Chill to 58 °F (14 °C).
Oxygenate, then pitch the yeast. After four days, allow fermentation temperature to rise to no more than 68 °F (20 °C) until fermentation is complete. Rack and lager for at least two months at or below 40 °F (4 °C).
Rack and allow the beer to drop bright, filtering or fining if necessary.
Rack the beer, prime and bottle condition, or keg and force carbonate.
