Session Sour

My latest sour project has been to start playing with Brettanomyces, and I was particularly inspired by Colorado brewery Crooked Stave's all-Brett fermentations. Lacking the cellar space of our old place, which allowed me to tuck a fermenter out of the way for a year or more, I was interested in what I’d read about conducting primary fermentations with Brett; when left to do the bulk of the work, it can ferment as quickly (or even more quickly) than a traditional Saccharomyces strain. The quicker fermentation seems to usually result in a reduction of Brett’s normal funky character, however.

I planned for a session beer grist to further promote a quick fermentation; specialty additions of aromatic and Special B contributed to a gold-amber colour and possibly a little depth of malt character. Hops were minimal. Not having a lot of hands-on experience with the different strains (yet), I was intrigued by the pie-cherry descriptors used for Wyeast’s B. lambicus. To encourage the yeast to produce the character for which it’s known, I soured the wort overnight to drop the pH, mimicking what would happen in a more traditional sour fermentation that included lacto and/or pedio phase.

I brewed this literally just before we left for our Midwestern Christmas; I was chilling as DeAunn was loading the car (cos I’m a spectacular husband). It sat in the swamp cooler with the aquarium heater set to keep it fermenting warm(ish) for nearly a month before I got back; at that point, I cranked up the temp further, which yielded more activity. It should be pretty well ready to bottle; I just have to wait until my current cold abates so I don’t end up infecting it in the eleventh hour. Hoping this one turns out more like my raspberry Flanders red (success) than my regular Flanders (epic fail).

Session Sour

Batch size: 5 gallons
Projected OG: 1.043
Projected SRM: 12.8
Projected IBU: 10.2
Boil time: 60 minutes
Brewhouse efficiency: 88%

Grains
76.9% - 5 lb 2-row
15.4% - 1 lb Aromatic
7.7% - 8 oz Special B

Hops
.2 oz Columbus (13.9%) (60 min)

Yeast
1 qt Lacto starter
1 pkg WY5526 Brettanomyces lambicus (no starter)

Extras
1 tsp Irish moss (10 min)
1 tsp Yeast nutrient (10 min)

Water additions (mash)
5 qts RO water

Brewday: 20 December 2011
Mash: 156F for 90 minutes
Pre-boil volume: 6.1 gallons
Pre-sour SG: 8.2P (1.033)

Cooled wort to 110F & pitched lacto starter. No plastic shielding the wort surface. Kept warm for 11 hours, then boiled as usual.

No real sourness noted before boil, but as the wort came up to boiling, a light but firm citrus aroma was present. Post-boil wort tasted lightly tangy.

Fermented in swamp cooler at 68F ambient

15 January 2012: Some bubbles & yeast colonies on surface. Bumped ambient temp to 76F.  Noticeable jump in activity after a few hours.  After several days, cooled it down to upper 50s; following that, brought it out to warm up for bottling, but haven't yet had a chance to do so.

Bottled (gallon jug): 17 February 2012
FG: unmeasured
Fermented kettle extras in a Carlo Rossi jug.  Thought it was working on an acetobacter infection, but upon further inspection it seems to have been starting a Brett pellicle; the main batch is doing the same thing.  Will leave the main batch to see how it develops; bottled the small batch to check progress.
Bottled 3/4 gallon with .6 oz table sugar and rehydrated champagne yeast.

14 March 2012: Bottles from Rossi jug carbonated well, but were pretty thin and only exhibited a little sourness and Brett pie cherry character.  To encourage more Brett character to develop (and to hopefully enhance a pretty lifeless beer), added 15 fl oz concentrated Montmorency cherry juice.  Visible activity within a few days; will give it another couple months before checking on it.

One distributor notes concentrated cherry juice at 68 brix; have not factored in its impact on gravity.

Bottled: 15 June 2012
FG: 1.009
ABV: 4.4%

Bottled with 4.3 oz table sugar and rehydrated champagne yeast.

Tasting:  Freaking fabulous.  Quite tart (lacto) with cherry following and a hint of malt underneath.  This has been a great year-round beer, and while it's not for everyone, it's been very popular with sour fans.  A rebrew is currently underway.