Death and Gravity

Beer image

After reading about beers brewed with wine yeasts and brettanomyces at both Bear Flavoured and The Mad Fermentationist I really wanted to try it myself.

The result is Death and Gravity, an old ale fermented with Lalvin K1V-1116 and brettanomyces cultured from the dregs of a few bottles of Orval.

The combination of wine yeast and brett is interesting for a couple of reasons. First, wine yeasts produce a range of toxins which are deadly to most ale strains. Brettanomyces, however, is not susceptible to these toxins and so can happily co-exist with it. Second, wine strains are, by-in-large, unable to ferment maltotriose and so leave lots of complex carbohydrates to feed the brett. K1V-1116 is primarily a white wine yeast and the original "killer" strain, it should produce a fruity end result with minimal hydrogen sulphide. This said, my basement smelled terribly of rotten eggs for the first couple of weeks of fermentation!

I mashed pretty high, aiming for a 68°C mash to get lots of complex carbohydrates for the brett. My plan was to extract as much of the sugars from the mash as possible and then to boil down to my target gravity. With this in mind I extracted 30l of wort at 1.060 which I boiled for 140 minutes to end up at 21.5l at an original gravity of 1.082. I hopped with a bit of Magnum and Saaz, with the malty grain bill and long conditioning time I didn't bother with much in the way of aroma hops. I racked the wort into a fermenter and pitched the K1V-1116 and the brett.

While planning this beer I visited my good friend Al (Hopsinjoor) in Manchester and got some oak cubes from used rum barrels from him. After 5 weeks in primary I racked the beer into 2 12l PET carboys and added the oak cubes as well as the rum I'd used to sanitise them. Now the beer gets a minimum of 6 months to mingle with the oak and the rum. So sometime in spring 2015 I expect to get to bottling this beast.

Vital Details:
Batch size: 20l
Expected OG: 1.081
Expected FG: 1.018
Expected ABV: 8.3% (+0.5% from rum)
Colour (SRM): 18.2
IBU: 37

47.2% (3.5 kg) Halcyon Pale Ale
40.4% (3.0 kg) Munich
6.7% (0.50 kg) Carared
3.4% (0.25 kg) Flaked Oats
1.4% (0.10 kg) Special B
0.9% (0.07 kg) Black Malt

Magnum (25g / 33 IBU) @ 60 min
Saaz (20g / 4 IBU) @ 20 min

Lalvin K1V-1116
Orval dregs

Yeast nutrient @ 15 min

Toasted rum barrel oak cubes
225ml dark rum