Motor Oil Belgian Stout - Brain Sparging on Brewing


Sour beer, saisons, farmhouse beer, homebrewing, ramblings

November 27, 2012

Motor Oil Belgian Stout

I brewed this beer almost a year ago in January of this year and although I was happy with the flavor, one thing I really disliked was that it seemed thin. (I know, smart people are going to scroll down to the recipe and point out that there isn't any flaked barley but not all stouts actually do use flaked barley and the oats and wheat is almost 20% of the grain bill, that is definitely enough body-adding grain.) It was what set me down the path of recognizing my stovetop BIAB method for one gallon batches wasn't producing the kind of beer I wanted. This second batch is getting mashed in my new two gallon cooler, which seems to be doing a better job of maintaining temperatures.

The first run of the recipe earlier in the year was just to see how it tastes in preparation for it's final destination. I like the flavor, it has some good roast character mixing with chocolate, raisin, oat-silkiness, some bready wheat character all over great Belgian yeast esters. However, it was not intended to be a stout all on its own. This beer is one half of a blended stout and sour beer based loosely on New Belgium Clutch, which is a blend of an imperial stout and the dark sour beer they use in their sour beers (most prominently seen in La Folie). It is a delicious blend of 80% imperial stout and 20% sour. So I began conceptualizing a more session-strength version of this blend, using a more moderate Belgian stout and a darker sour beer. The dark sour beer was brewed in the beginning of this year and innoculated with dregs from my lambic. I published the recipe for it under the name Battery Acid. I'm still considering the proper blending percentages. I've thought as high as 50/50% and as little as 75/25 with 25% sour. Since the stout portion won't be done for a few weeks I'll have time to lock down how sour I want it to be and how much of the sour portion I want to bottle straight. I'll write separately about that when the time comes.

So today I'll just post the recipe for a tasty, wheat-driven Belgian stout. It uses a lot of unconventional grains for a stout. I blended the concepts of the usual Irish and English stouts with new wave Belgian stouts, in particular Boulevard's Dark Truth, which I enjoy a lot. The recipe uses chocolate wheat, which is a fairly new grain and one that gets universal appreciation. It is smooth and chocolately and bready all at the same time. It's quite tasty. It's a good mix with chocolate malt to get those chocolate flavors but limiting the roasty character of chocolate malt. Although I haven't used it in a dunkelweizen it would probably be fantastic.

Anyway, here's the recipe for one gallon:

Motor Oil Belgian Stout
Est. ABV: 5.51%
IBU: 35.2
SRM: 54.3
OG: 1.054
Est. FG: 1.012

Water Profile: London
RO water adjustments:
Chalk: 0.5g
Calcium chloride 0.5g
Epsom salt 0.5g
Baking soda 2g
Kosher salt 0.5g

Mash water: 0.63 gallons at 170F -- mash 60 min at 158F
Sparge water: 1.57 gallons at 174F

1lb Marris Otter 49.26%
0.25lb Crystal 120l 12.32%
0.25lb Flaked oats 12.32%
0.13lb Chocolate malt (350 SRM) 6.4%
0.13lb Chocolate wheat malt 6.4%
0.13lb Wheat malt 6.4%
0.07lb Carafa III 3.45%
0.07lb Roasted barley 3.45%

Boil additions for 60 minute boil:
0.4oz EKG [5%] at 60 minutes

Pitch on cake of South Austin Golden Strong yeast at 75F, ferment at ambient for three weeks.

This recipe is one of my more complicated recipes. I am usually an advocate of less-is-more when it comes to recipes because too many grains tends to produce a muddy beer when people try to add too many flavor components. I'll rationalize this one: MO is your base grain, which you need. The oats add body to the beer and if it wasn't oats, I'd add flaked barley. The chocolate malt, chocolate wheat malt and wheat malt should be thought of as two flavor components rather than three. The wheat and chocolate wheat malts produce body and breadiness. The chocolate wheat and chocolate malts come together as a blend of chocolate flavors with some roast but a bit smoother than chocolate malt on its own. The crystal malt and roasted barley are flavor additions and the carafa III was to get it over-the-top dark, there's no significant flavor addition there. So the resulting flavors you get are: raisin/caramel from the crystal, roast from the roasted barley, bready from the MO wheat and chocolate/coffee from the chocolate malts and mouthfeel from the oats. Those are four distinct enough flavors in a balance that isn't muddy but rather distinct. It's definitely on the edge of too much going on, especially with the yeast, but doesn't reach muddy. It may be too much with the sour beer added but we'll see.


  1. I'm curious about your blending strategy. New Belgium pasteurizes their sour stuff before bottling, but what will you do to prevent the sour portion from turning the stout portion sour itself, and over-carbing in the bottle?

    1. I intend to write more about it but right now I am leaning towards a method I picked up from Mike T./Oldsock/ to add finings and cold crash the sour portion, rack to another fermenter, hit with campden for 24-48 hours and then blend from there. I'll reyeast the straight portion and blend the rest into the stout and the ale yeast will provide carbonation. Alternatively I could bottle the blend, wait three weeks for carbonation and then bottle pasteurize on the stove but I'm not too hot on that idea. I haven't completely ruled it out but I'm 95% in favor of the first method.