[dcb]

I'm re-posting a question from the recipes section in the hopes it will attract some comments.  I'm just bottling my first brett beer and very puzzled about something.

It was brewed in June with an OG of 1.073 and fermented down to 1.012 in just over two weeks.  I racked to secondary and pitched Brett. b, where it sat for some 5 months at about 65F.   This weekend I sampled again, and while the flavor is quite different and largely as expected, the SG is still at 1.012. 

My (admittedly simplistic) picture of it was that brett is able to metabolize sugars that are not fermentable by Saccharomyces, and I expected the SG to drop by at least a few points. Clearly something has been going on, but it doesn't match my model of how this works.  What's wrong with my understanding?


(My original thread: https://www.homebrewersassociation.org/forum/index.php?topic=19667.0)

[morticaixavier]

Brett does metabolize sugars sach yeasts cannot but some of the more complex carbs will take a very long time. I'm not sure why you haven't seen a gravity drop in that time. I do know that a lot of the flavor development attributed to brett has nothing to do with it consuming sugars. It develops a lot of the flavor characteristics from metabolizing esters and other yeast byproducts. This reaction would not reduce your gravity at all.

[reverseapachemaster]

I am surprised to see no reduction in gravity after five months but that could be related to your mash schedule or brett pitching rate (although it sounds like you pitched a whole vial of brett). Jonathan is right; you can get flavor development out of brett without any reduction in gravity because brett works on esters and other flavor compounds to create new flavors and that process does not require fermentation of carbs.

Are you sure your gravity readings at the end of the sacc fermentation or your most recent reading were accurate?

[dcb]

Well, it's oddly comforting to know that my expectations weren't out of line.   I appreciate the confirmation in that-- thanks!

Are you sure your gravity readings at the end of the sacc fermentation or your most recent reading were accurate?

I'm pretty confident in them, though my confidence in the July readings are based more on trust in my practices (and hopefully not too much wishful thinking).  This weekend, I let my sample sit on the counter long enough to come to room temperature, so I was within a degree or two of 68F.   I let the little bit of foam fall flat, giving the hydrometer a twirl and making sure it's free floating.  I haven't checked it in distilled water since Summer,  but I think I treat it with reasonable care.  I did notice that the sample was slightly effervescent when drawn, but it  sat out 45 minutes before I took my last reading so I doubt there's much error from that.

Not I'm thinking I'll pick up some distilled water tonight and re-check my hydrometer.  It'll be worth it to get another taste of the beer.

[brewinhard]

What temperature have you been keeping this beer at with Brett B. in the secondary? 

[dcb]

What temperature have you been keeping this beer at with Brett B. in the secondary?

It's been under my stairs in a basement, where it's a pretty steady 66F.

BTW, my hydrometer checked out just fine with distilled water and I was able to reproduce my last hydrometer reading.  No way to go back and prove the original reading, so I'm left with something I can't explain.

Now I'm twitchy about bottling out of fear that the brett will take off and .  I'm not nearly as concerned about exploding bottles and flying glass shards as I am wasted beer, though either is bad.   Mostly I just hate it that my understanding is so disconnected from my observations.

[ynotbrusum]

That is a bit on the cool side for Brett, but it wouldn't be dormant at that temp IMHO.  I have my spring Flanders Red held in my basement year round, then about this time of year I blend it with a smallish pull from my solera in a bourbon barrel.

But I use a dedicated 3 gallon keg for this purpose, so bottle bombs are not a worry.

[brewinhard]

Yeah, those temps are more than acceptable for brett to finish up in a reasonable amount of time.  Now you got me puzzled too...

[klickitat jim]

Its either dead brett or an instrumentation fault. Just a guess

[dcb]

Its either dead brett or an instrumentation fault. Just a guess

Ah yes.  Sometimes someone just needs to blurt out the obvious.

While I trust the current calibration of my hydrometer, there's no way to go back and prove that I didn't either gaff the reading or mis-record it. 

But if it's dead brett, it seems like I ought to be able to prove that.  My first thought was to make a small starter wort and pitch a sample of the beer in there, but that would only show whether I had live yeast, not live brett.

Hmmm.....

[brewinhard]

Brett is pretty hard to kill especially if you pitched a vial/pack directly into the fermenter.  Do you remember how old the brett was at pitching (the secondary brett that is)?

[dcb]

I don't remember checking the date on the pack specifically, though I have a knee-jerk habit of looking at the date (which of course proves nothing about this specific instance).   I believe the brett is active because the difference in taste is striking, but I thought the idea that the brett was dead was a pretty sensible thing to consider.

[klickitat jim]

Since I'm playing the part  of Capt Obvious, i suggest checking calibration and then test another sample. if your hydrometer reads 1.006 in water then probably the bret beer is done.

[ynotbrusum]

6 points is a lot off the mark, but possible.  I have one that is 4 points off...

[trentmark]

I know this is going to sound crazy but it has worked consistently to stimulate Brett several times for me. Try adding some pelletized hops. I often brew (sometime award winning) saisons finished with Brett and a little dry hopping does this style a favor. The first time I realized the effect, I had a secondary pitched to Brett for about 2 weeks with no apparent activity. A couple of days after adding the dry hops, fermentation activity was apparent. I've repeated this process at least 5 time with the same results. After adding the hops, final gravity is reached in about 4 weeks. I've done this with Brett pitching gravities from 1.008 to 1.015 to finish from 1.002 to 1.004. For my taste, I use Brett fermentations at 60F, so your temp is fine (more funk, less fruit at higher temps). I normally use 0.5 to 1 ounce of Saaz.

My theory is the pelletized hops have trapped air in the pellets and this stimulates the Brett.