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Brettanomyces Bruxellensis var. Drie

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I was lucky enough to get my hands on a 5-gallon sized pitch of Brewing Sciences Institute’s Brettanomyces Bruxellensis var. Drie, aka “Brett Drie”. Up until the recent Brett Trois controversy, a horse that has been beaten to a pulp, most of us thought Drie was the same strain as WLP644 Brettanomyces Troisaccusations that have recently been confirmed by White Labs for those still unconvinced. Despite one being S. Cerevisiae and the other Brettanomyces I was still curious to see if the two strains shared any similarities that may have caused folks to think they were the same initially. Or maybe we all just blindly believed they were the same and kept passing along misinformation.

That never happens, does it?

So I brewed a split batch pale ale half fermented with Drie and half with Trois to see what, if any, similarities the two cultures shared.

Brettanomyces Trois and Brett var. Drei
Is it spelled “Drei” or “Drie”? Im so confused

For the comparison, I brewed the HopWards recipe, with some minor hop selection changes that aren’t important to this post. The recipe has plenty of Oats in the grain bill to retain somebody for the non-glycerol producing Brett strain, Trois tends to need a boost in body as well. Being that I’m a big fan of the strain and using it regularly I had plenty of fresh Trois slurry, but I felt I had to build up the Drie a little more. BSI packages the yeast in these little pouches that come with a vial of sugar solution that you’re to feed to the pouch 8-12 hours prior to pitching. It really might be a pitchable quantity after that sugar addition but I felt more comfortable feeding it an extra 500 ml of starter wort right into the pouch, just in case. The pitching rates ended up as a bit of a guess here because I wasn’t sure how many cells came in the BSI pack, but it should be more than sufficient for a beer of this gravity.

mash recirculation
A sparge arm would be on fleek.

Going into this I was kind of expecting the two strains to be pretty similar, having used Trois a great deal over the years I knew exactly what to expect, but as soon as I took a whiff of the Drie starter there were dramatic differences in aroma. Trois smells overwhelmingly like a tropical fruit drink and while Drie has the tropical fruit aromas it also throws off a rustic, funky edge to it that’s so very distinctly Brett. Made me wonder even more if anyone who had claimed the two cultures were the same had ever used the two at all, let alone for a side by side comparison. 

Neither batch received any o2 other than my pumping into the fermenter, I know Trois can handle that and with Drie (and all Bretts) I’m afraid of the acetic acid boogie man. The Trois batch was fermented out and kegged in two weeks with an FG of 1.011, dry-hopped, and put on tap within three weeks of brewing. The Drie portion took a little longer to wrap up and stayed in the primary for ~4 weeks until it reached a terminal gravity of 1.012 (OG was 1.054 by the way). The AA% was about what I would expect from a 100% Brett fermentation, and just about exactly the same as Trois. I packaged a couple of bottles of both the Drie and Trois variants prior to dry hopping for a better analysis down the road, as well as to see how the Drie ages under the rigors of bottle conditioning. 

brett drie beer fermenting in better bottle
Early signs of fermentation.

Tasting Notes/Comparison:

Brewday: 2/22/15
Kegged:  Trois – 3/8/15
Kegged:  Drie – 3/26/15
Notes:     4/26/15

Taking the first whiff of the Drie version I am getting smacked in the face with aromas of Mango, pineapple, papaya, mostly very soft stone fruits. Bordering on spoiled fruit everything is of the overripe variety with a rustic peculiar funk to it. Its almost as if you blended a bunch of fruit into a smoothy while sitting in a dingy mildewy basement. While the Trois version has sharp/bright fresh peach, orange, etc, Drie has more of a peculiar fruit character. A slightly similar beer in aroma but Drie favors more rusticity to Trois’ bright fruity tropical bomb. Similar to when I wafted the Drie starter, it is unmistakably wild on the nose that upon first whiff you think its Brett fermented, not so for the Trois version. Actually the Drie starter smells almost exactly like the beer, which is almost never the case.

Mouthfeel of the two beers is nearly identical, they have a soft wheaty oaty body and very very slight dry sharp bitterness on the front of the tongue. The oats are very prominent in the middle of the mouth then the finish starts with a kick in the top back of the throat and then fades back to the wheaty/oaty pillowy softness. The beer as a whole is very soft, nothing overwhelming. Where the two differ is in the finish, the Trois version has a more crisp dry finish where the Drie version hangs onto the Oaty/wheaty character a bit longer than I enjoy. Despite the FG of the two being nearly identical I think the Drie version needs to be more dry, especially with the significant body that remains. It does drink very easily though, the beer is quite good but the finish on it could get a little boring if you have more than a few glasses. 

glass of beer on table
Check out that bakers table I’m restoring!

Trois just works so much better in this beer, the funkiness of Drie actually seems to clash with the tropical fruit nature of the base beer. I quite enjoy the Drie version but the Trois version is what I am shooting for with this recipe. The proof is in the pudding as I kicked the Trois keg in a few weeks while the Drie variant remains on tap. This is not to say I do not like the B. Drie strain, I actually thinks its one of the most unique Brett strains I have used and have since pitched it into 5 beers since this batch. Its been added to barrels, and soon to added to secondary on a few wacky weird Saisons so this pitch will be going quite far.

Sure, the two strains share some similarities, specifically in the fruity aroma department, and seemed to exhibit similar tendencies in fermentation, i.e. AA%, body, etc. But when you drink the same beer fermented with each culture side by side it’s obvious that they are not the “same” (not earth-shattering news here I know). Drie is more classic Brett than I had imagined it would be, but with the fruity esters it throws off I can see it being very versatile strain for my beers. Both of these strains are going to work for me just fine, yes sir. Did anyone ever do a sensory analysis of the two strains or was this Trois=Drie rumor just a whisper down the lane kind of thing, I’m thinking the latter. 

***I realize that BSI Drie is not available to homebrewers and thus this information may not seem useful but I have reason to believe that it will be available soon. A lot of us have been interested in this culture for quite a while but even more so in light of the reclassification or Trois (that’s a good beer name btw) and I know a few labs have noticed the demand from folks. I am not ready to jump to the conclusion that the newly “released” WLP648  Brettanomyces Bruxellensis Trois Vrai is the same as BSI Drei, but I do plan to put them through some sensory analysis to see how similar they are. We don’t want to spread any more misinformation now do we?