The Brewer

Kölsch: The Ale That Thinks It's a Lager

Kölsch: The Hybrid Hero

Kölsch is a protected geographical indication (PGI) in Europe. Technically, you can only brew “Kölsch” if you are within 50km of Cologne (Köln), Germany. If you brew it elsewhere, it’s a “Kölsch-style Ale.”

But whatever you call it, it is brilliant. It uses top-fermenting ale yeast (warm), but it is conditioned (lagered) at cold temperatures.

  • Result: A beer with the subtle fruity complexity of an ale, but the brilliant clarity and crisp finish of a lager.

The Guidelines (BJCP 5B)

  • Original Gravity (OG): 1.044 – 1.050
  • Final Gravity (FG): 1.007 – 1.011 (Very attenuated)
  • ABV: 4.4% – 5.2%
  • IBU: 18 – 30
  • Color: Very Pale Gold.

The Ingredients

Malt

Kölsch is arguably the palest beer in Germany.

  • Pilsner Malt: 90-95%. Use a high-quality German variety.
  • Wheat Malt: 5-10%. Adds a touch of breadiness and helps head retention.

Hops

Subtle German Nobles.

  • Varieties: Hallertauer, Tettnang, Spalt.
  • Usage: Mostly a 60-minute bittering addition. Flavor hops should be barely perceptible.

The Yeast: The Secret Weapon

You cannot brew a Kölsch with US-05 or a Lager strain. You need a specific Kölsch strain.

  • Wyeast 2565 (Kölsch): Acidic, tart, highly flocculent (eventually).
  • WLP029 (German Ale/Kölsch): Crisper, closer to a lager profile.
  • K-97 (Dry Yeast): A fantastic dry option that produces excellent foam.

These strains produce a very specific, delicate fruitiness—often described as “white wine” or “pear”—that defines the style.

The Process: Hybrid Fermentation

This is what makes it a Kölsch.

  1. Mash: Single infusion at 149°F (65°C). We want high fermentability for a dry finish.
  2. Boil: 90 minutes (Pilsner malt = DMS risk).
  3. Ferment Cool: Ferment at the very bottom of the ale range: 58°F - 62°F (14°C - 17°C).
    • This suppresses heavy esters, leaving just that whisper of fruit.
  4. Lager: Once fermentation is done, crash it to 32°F (0°C) and hold for 3-4 weeks.
    • This “lagering” phase drops the yeast and proteins, creating the brilliant sparkle Kölsch is famous for.

The Stange: Serving Ritual

In Cologne, Kölsch is served in a Stange (“Rod”), a tall, thin, cylindrical glass holding only 200ml (about 7 oz).

  • Why so small? So you drink it while it’s still cold and carbonated.
  • The Köbes: The waiter (Köbes) carries a special tray (Kranz) with holes for the glasses. They will wordlessly replace your empty Stange with a full one and mark a tick on your coaster.
  • Stop: To stop the flow of beer, you must place your coaster on top of your glass.

Water Chemistry

Cologne water is fairly soft but has some mineral content.

  • Calcium: 50 ppm.
  • Sulfate/Chloride: Balanced or slightly Sulfate-leaning to enhance the crispness.

Troubleshooting

  • Cloudy? Kölsch yeast is “powdery” (low flocculation). You must cold crash and lager it long enough, or use finings (gelatin/biofine). A cloudy Kölsch is technically a “Wiess” (an older, unfiltered style).
  • Too Fruity? You fermented too warm. Keep it under 62°F.
  • Sulphur? Common during fermentation. It will fade during the lagering phase.

Summary Recipe: “Domplatte”

  • Grains: 9 lbs German Pilsner, 1 lb Wheat Malt.
  • Mash: 149°F for 60 min.
  • Hops: Spalt to 25 IBU at 60 min.
  • Yeast: Wyeast 2565.
  • Schedule: Ferment at 60°F for 10 days. Cold crash. Lager at 33°F for 21 days.

Kölsch is the perfect “lawnmower beer” for the beer snob. It’s refreshing enough for a hot day, but complex enough to keep you interested.