Monday, November 8, 2010

Brewing the Imperial Chocolate Oatmeal Stout

On 7 Nov. 2010 I brewed a Imperial Oatmeal Stout that I bittered with cacao nibs.  Brewing commenced at 8 a.m. with boiling water for storage in a the hot water tank (i.e., modified 40-qt cooler).  The grain bill is as follows:

15.00 lb Pale Malt (2 Row) US (2.0 SRM) Grain 72.29 %
1.25 lb Barley, Flaked (1.7 SRM) Grain 6.02 %
1.25 lb Chocolate Malt (350.0 SRM) Grain 6.02 %
1.25 lb Oats, Flaked (1.0 SRM) Grain 6.02 %
0.50 lb Black (Patent) Malt (500.0 SRM) Grain 2.41 %
0.50 lb Caramel/Crystal Malt - 60L (60.0 SRM) Grain 2.41 %
0.50 lb Caramel/Crystal Malt -120L (120.0 SRM) Grain 2.41 %
0.50 lb Roasted Barley (300.0 SRM) Grain 2.41 %

It took me around 2 hours to crush the grain and get all the water heated for the mash.  After I added the grain to the mashtun (i.e. modified 70-qt. cooler), I added 180 °F water to the grain and kept the grain at 158 °F for approximately 90 min.

The temperature was a little higher than called for, but I wanted somewhat of a sweeter beer that had more sugary malts extracted from the grains. After draining the mash, the grains were sparged with 180 °F water to get approximately 8-gallons of wort.


By this time I opened a bottle of Avery Brewing Company's "The Czar" Imperial Stout (review is the previous blog). The boil lasted 90-minutes.  I added the following to the boil:

1.00 oz Chinook [13.00 %] (45 min) Hops 26.4 IBU
1.00 oz Chinook [13.00 %] (20 min) Hops 22.7 IBU
8.00 oz Cacao nibs (15 min.)
1 tsp. Irish Moss (15 Min.)
1 Capsule Yeast Fuel (10 Min.)

After super cooling for 30 min. to about 80 degrees I transferred to my primary fermenting bucket.  Pouring the wort from the boiling kettle to the bucket, to ensure proper oxygenation for the yeast.  I added the following yeast to the wort:

1 Vial Super High Gravity Ale (White Labs #WLP099) Yeast-Ale 
1 Vial Irish Ale (White Labs #WLP004) Yeast-Ale  

Total cost was around $20 for the specialty grains.  I already had a ample supply of base malt thanks to my friend Scott and a harvest of hops from the hop vines that was planted this past spring at my parents up in Michigan.

Gravity readings were as followed:

Pre-Boil: 1.064
Original Gravity: 1.090

That gave me only 58% efficiency.  I need to find a way to up my efficiency to around 75%, maybe a harder boil or change to fly sparging instead of batch sparging.  If my final gravity is around 1.023, I will have a 8% beer.  It was a  good day to brew and had a good session.


  1. Sounds like it! Glad to hear your hops came in alright, and your backyard brew setup looks like a nice place to chill on a Sunday morning.


  2. Thanks Alex! It is a nice place to hang out on a sunny day and brew beer!