Kepler’s Kölsch

Kepler’s Kölsch

(5 gallons/19 L, partial mash)
OG = 1.047 FG = 1.009
IBU = 22  SRM = 6  ABV = 4.9%

Ingredients
3.0 lbs. (1.4 kg) Pilsner malt
0.5 lbs. (0.23 kg) Vienna malt
0.5 lbs. (0.23 kg) wheat malt
1.0 lb. (0.45 kg) Muntons Light dried malt extract
2 lb. 13 oz. (1.3 kg) Muntons Light liquid malt extract (late addition)
1⁄4 tsp calcium chloride (60 min.)
1⁄8 tsp yeast nutrients (15 min.)
5.5 AAU Tettnang hops (60 min.) (1.2 oz./35 g of 4.5% alpha acids)
0.25 oz. (7.1 g) Hallertau Hersbrücker hops (15 min.)
Wyeast 2565 (Kölsch) or White Labs WLP029 (German Ale/Kölsch) yeast (3 qt./~3 L yeast starter @ SG 1.035)
1 cup corn sugar (for priming)

Step by Step
In a clean bucket, combine 6.0 gallons (23 L) of very soft (or distilled) water with a teaspoon of calcium chloride and a teaspoon of gypsum (calcium sulfate). Add a Campden tablet (for removal of chloramines), cover loosely and let sit overnight. This is your brewing liquor. Place grain bag with crushed grains in a 2-gallon (7.6-L) beverage cooler. Heat 5.5 qts. (5.2 L) of brewing liquor to 163 °F (73 °C) and stir this into grains. Mash grains, starting at 152 °F (67 °C),
for 30 minutes.

While mash is resting, stir dried malt extract into 1.0 gallon (3.8 L) of brewing liquor in your brewpot and heat to 148 °F (64 °C). Also heat 5.5 qts. (5.2 L) of brewing liquor (for sparge water) to 180 °F (82 °C) in a separate pot. Run off first wort from cooler and pour into brew pot. Continue to hold the temperature at 148 °F (64 °C).

Add sparge water to cooler, rest 5 minutes then run off second wort. Add the second wort to your brewpot and hold at 148 °F (64 °C) for another 10 minutes. (The enzymes from the partial mash wort will continue to work on any remaining  degradable carbohydrates from the grain and malt extract, leading to a more fermentable wort.) Add about a half-gallon (1.9 L) of your brewing liquor to your sparge water pot and bring it to a boil. Add calcium chloride and bring wort to a boil. Once you see the hot break form, add hops and boil for 60 minutes.

Every 10 minutes, top up the boil to its original volume (around 2.5 gallons/9.5 L) with boiling water. (This will help minimize wort darkening by keeping the wort from getting too thick. If you can boil more than 2.5 gallons/9.5 L vigorously, do so.) With 15 minutes left in the boil, add the final dose of hops and yeast nutrients.

At the end of the boil, stir in liquid malt extract and let wort steep (with lid on) for 15 minutes before you begin cooling. Cool wort until outside of brewpot is cool to the touch. Combine with cool brewing liquor in your fermenter to make 5 gallons (19 L) of wort at 65 °F (18 °C). Aerate well and pitch yeast sediment from yeast starter. (Note: If don’t make a starter, pitch two — or better yet three — packs of liquid yeast.)

Ferment at 65 °F (18 °C), then rack to secondary and cold condition at 40 °F (4.4 °C) for three weeks or until beer falls clear.  Bottle with corn sugar or keg and carbonate to 2.4 volumes of CO2. Serve in a Kölsch glass (stange), if you have one.