Stuck Fermentation with 3711 (I know, right?)

Hey, all.

I've been lurking here for a while now, but this is my first actual post. So, cheers, everybody!

My problem is this: I have a partial mash Saison fermenting right now, with an OG of 1.056, and it's not budging (almost a week now) from the SG of 1.025.

Here's the skinny: it was my first partial mash; I mashed a pound of Vienna, half a pound of Belgian Biscuit, and a quarter pound of flaked wheat for one hour probably a little too high (ca. 158*). Then I did an hour boil, adding two pounds of Munton's Wheat DME at the beginning and four pounds of Breiss Pilsner DME at 15 minutes (then waited for another hot break). There was a bit of a boil-over at this point.

Afterwards I chilled it down to about 70* and pitched the 3711 straight from the smack pack (after it had been out for about 4 hours). I got vigorous fermentation and about two inches of kraeusen by the following morning, steady fermentation for the following four or five days, and then it petered out. This was all simply at room temperature, about 68*. When I checked the SG a few days later (after about a week total had passed), it was at 1.025. It hasn't moved since. I took it up to my room to warm it up - to about 75* - and nothing; I upset the yeast - nothing.

No matter how I spin it, I can't figure out why the fermentation's stuck. Any suggestions?

Many thanks!

 

Off the top of my head, only 2 things: pitched yeast too soon & stressed them OR your hydrometer is off. 158F on 20% of your fermentables with 3711 = no way there's enough dextrines to hit 1.02+

 

did the pack start swelling? i'm drinking a saison with 3711 right now, with very similar ingredients and mashed specialty grains at 156, so close. came down to 1.008 @ 69 degrees. pitched after about 6 hours

 

Did you aerate properly?

 

I would check both your thermometer and your hydrometer for accuracy.

3711 is such a beast that it will fermemt the spoon if you stir too long. The temp is fine. If your thermometer and hydrometer check out, then slowly warm it up and it should finish out. I have used 3711 a lot and it always finishes low with no problems.

 

beergolf is spot on. I have never had an issue with 3711, it takes off like crazy and doesn't stop until everything is gone.

 

lol, nice one :fro:

 

Yes, it was quite swollen when I pitched.

Yes, I aerated it both as the word was going into the carboy and then shook the carboy for 1-2 minutes twice before attaching the airlock.

I've checked the hydrometer against my tap water and discovered it read .005, so I've been subtracting that from all its measurements; but it's gotten both my brown ale (1.020, modified down) and my rye pale (1.012, modified down) right where they should be; and it's certainly not misreading those by as much as .015. I raised the temperature up to 75, do you think that was insufficient and I should raise it to 80 or so?

Thank you all for taking the time to help me out!!

 

Any more activity since you raised the temp?

 

Nada. I'm thinking I must have simply underpitched, maybe combined with not enough aeration - but only because I'm always paranoid about under-aerating my wort. I've made a starter of some champagne yeast, I'll be pitching it later today, we'll see if that dries it out a bit.

 

It makes no sense unless you got a pack that was handled poorly. Wyeast even recommends using 3711 to restart a stuck fermentation. That stuff usually just chews through anything. 1.056 is not a very high OG.

 

I usually underpitch this yeast to get more flavor out of it; did you add yeast nutrients to the boil?

 

go ahead and try that, but it might not do much. champagne yeast can only ferment simple sugars (like sucrose), it can't digest maltose. i would assume that the 3711 ate the simple sugars already, so the champagne might not have anything to work on. if that's the case, it'll just drop out after a few days.

but please let us know if it works, always good to learn something/be proven wrong.

 

The champagne yeast definitely did basically nothing. And I agree that the 3711 shouldn't have stopped, but it did, for some reason.

That said, I do have news: I bought another pack, made a starter (and split it between two stuck batches - I have all the luck), and put it in a ca. 80* water bath and it's bubbling pretty consistently now. Hopefully the roommates won't mind too much, and it should be dried out in a couple days! I pitched it yesterday and it dropped 3-5 points as of this morning, and that was before the bath. I think this beer if finally on its way; I just hope it survived all the jostling and failure up to now!

I'll be sure to keep you all updated as things progress. And thank you again for all the advice!