Imperator

The Imperator Doppelbock is a classic German Doppelbock that is comparable to Spaten's Optimator without trying to be a clone. It is of a dark mahagony color without roasted notes in aroma or taste. Though intended to be complex in flavor it is also very drinkable. Mostly due to its starting extract of 18.5 Plato which puts it in the lower end of the range for Doppelbocks, but most commercial examples are fairly close to that range. This beer will take some time. After lagering it for 2-3 months, it should be aged for at least another 2-3 months for the dark fruit notes to come out.

The traditional season for Doppelbock is Lent, which is the time from Ashwednesday to Good Friday. Ashwednesday is generally towards the end of February. This means that the best time to brew this beer is September. This will give it 6 month to be ready for its season.

Water

for brewers who build their own water

This water treatment is for 34.5 l reverse osmosis water:

• 0.90g Table Salt (NaCl)
• 0.65g Epsom Salt (MgSO₄7H₂O)
• 2.00g Baking Soda (NaHCO₃)
• 3.80g Chalk (CaCO₃)

The resulting water should have a profile of: 48 mg/l Ca, 3 mg/l Mg, 30 mg/l Na, 9 mg/l SO₄, 20 mg/l Cl, 131 mg/l HCO₃

While it is not important to match this water profile exactly, the following guidelines should be followed:

• residual alkalinity should be around 4 dH (degree German Hardness) or 80 mg/l HCO₃
• the sulphates should be low since this beer doesn't emphasize the hops
• Calcium should be at least 40 - 50 mg/l since it is a yeast nutrient

Grist

• 15% Weyermann Bohemian Pils
• 75% Weyermann Munich Type II (Dark Munich)
• 2% Weyermann Cara Aroma
• 3% Weyermann CaraMunich II
• 2% Weyermann CaraMunich III

The Pilsner malt, can be substituted with regular German Pils malt, was added as an insurance against excessive enzyme degradation during the decoction process. The CaraAroma could be omitted if not available. To increase the complexity of this beer, I like to layer different crystal malts. In this case Weyermann's CaraMunich II and III.

Use your batch size and brewhouse efficiency to determine the grain amounts necessary to reach a post boil gravity of 18.5 Plato (~1.074 SG)

Hops

for a 22l batch add about 2.4g of alpha acid (24g of hops with 10% AA or 48g of hops with 5% AA) 5-10 min after the start of the boil and boil for another 60 min. German Hallertauer Mittelfrueh or even Hallertauer Magnum will work well. The Tinseth formula estimated 22 IBU for this beer.

Yeast

WY2206 (Bavarian Lager) works well for this beer. For 19l (5 gal) pitch about 200 ml thick fresh yeast slurry. This slurry can come from a previous batch or a starter. Make sure it is fresh since a lot of yeast is needed to fully ferment this beer.

Primary fermentation

Cool the wort to 5-8 C and pitch the yeast after oxygenating the wort. You may give the beer another shot of oxygen after 10 - 12hrs if no activity is visible yet.