Stalled Fermentation

[MikeRoy]

Brewed a Belgian Golden Ale using White Labs Belgian Golden yeast. O.G. was 1.064 on friday(brew day). By Sunday evening it was down to 1.043, This morning (Tuesday) I checked the gravity again and it was at 1.043 STILL! Approximately 36 hours after the last reading...Fermentation temperautre was 68 F (which is the lower end of the spectrum for this yeast), I've since raised the temperature on my control panel to allow it to reach 74 F thinking that maybe this yeast might do better at a warmer temperature.

I've used this yeast before but never at this volume of wort (8.5 ish bbls), could underpitching be a cause? I wouldn't think so due to the fact that it took off like a rocket in the tank to start, if it was underpitched wouldn't it usually lag at the beginning and not mid-fermentation?

Any thoughts on why this beer, with this particular yeast would stop fermenting so soon??

How long would I want to wait before either trying to rouse the yeast with CO2 or pitching more yeast?


Many thanks in advance for your time and insight.

[Brew49411]

First, call White Labs. They are always helpful with suggestions. If it were me though, I would go ahead and give it a couple shots of co2. Under pitching doesn't sound like the problem.
Have you ever tried servo myces? It really helps you have a healthy fermentation.

[Larry Horwitz]

Hey,

that's the Duel strain I think...it always works like that...tears throught the first 75% or so and then stalls. Wait it out. I've seen it take as long as 6 weeks to finish. Trust me...it'll be worth it.

[Charles S.]

Yep it's a very slow finisher. White labs has a new golden strain that is much less temperamental. I don't have the number though.

[Todd]

Ardennes

Mike this is possibly a Belgium Ardennes yeast similar to La Chouffe and Duvel yeast in character but not in performance. I have used it with the same results. One thing we tried was pulling off some of the yeast and feeding it with freshly oxygenated wort and then repitching this back into the fermenter. With this minimal amount of attenuation you could diffuse some oxygen into the beer and still be alright. You could just wait and keep the tempurature high, but that is difficult to do as a brewer, I know!
Let me know how your filtering goes if you make it that far. If I remember correctly we had a tremedously diffficult time filtering as the yeast cell counts were still very high even after a 2 micron filter run!!
This yeast is difficult to use and I would recommend the La Chouffe yeast!!


-Todd

[MikeRoy]

I'm not planning on filtering this, just cold conditioning it first in the fermenter....whenever it decides to finish...then in a grundy. So clarity isn't an issue with me though attenuation is.

Thanks for the input so far, hopefully it will continue to slowly drop, I'm thinking if I don't see a change tomorrow I will charge it with some CO2. In the meantime the flavor is dead on from what I expected so there's nothing about the beer that's been affected negatively so far.

[Todd]

Co2

Mike,

I wouldn't wait on the CO2. The addition of CO2 will not have a deleterious affect on the beer so I would do that ASAP.

If there is no metobolic activity the temps will fall to ambient (NH might be cold now) and could finish (stall) the beer completely. If the thing stalls completely you might have to isolate the tank from the glycol loop and run warm water through the jackets to bring up the temp and repitch with a strain you are confident with (house??) or simply dump it and start over (with La Chouffe yeat). Hold off on all of this until you're at a complete loss.

You will notice this beer won't flocculate completely and you will be left with some continual flocculation resulting in some suspended autolyzed yeast character which will result in a bready/earthy note. I think it is part of the profile.

Let me know

-Todd

[beerbrewer]

I had the exact same thing happen to me this fall. I called White Labs they gave me some advice -rouse the yeast and wait. Which worked and the beer did eventually finish but it took some patience and a lot of worrying. The end product was fine but I roused by transfering the whole fermentation to a different fermenter. And had activity the next day. Good luck and call me if you want to know what the fermentation profile days points temp etc was.
Ben
Nashoba

[dick murton]

I realise this comment is far too late to save your beer, but it sounds like you have underpitched, and more importantly, under oxygenated. Stirring up with CO2 will not revitalise the yeast. All CO2 will do is stir the yeast up, and virtually as soon as you stop will drop to the bottom again. It needs oxygen, from air or pure oxygen. A far less likely possibility is that the yeast has run out of yeast nutrient, most commonly zinc. If is happens again - rouse it with air / oxygen, through a fishtail spreader.

Cheers

[gitchegumee]

Not to quibble with Dick, but I would not oxygenate a beer at this stage, preferring instead to repitch with fresh yeast and oxygenated wort. Belgian brewers tend to have pitching rates and oxygenation levels lower than normal and fermentation temperatures and yeast growth higher than normal. I think this helps define the ester profiles Belgian beers are famous for. Some of the Belgian yeasts respond poorly to fermenter attemperation and will crash easily upon any cooling. Instead of pitching at 68F, next time try 78F and letting it rise without cooling. As long as the yeast stays below 84-86F, you should have no problems. Cheers!

[MikeRoy]

UPDATE

So friday (Day 14) I made a slurry with the wort from the fermenter and some Nottingham Dry yeast in an attempt to attentuate the beer a little more. When I left the brewery on Friday the PSI Gauge read 5, this morning( Day 17) it was up to 10. After doing another reading it would appear it's dropped another 2 points and the fermenter was up 3 degrees( from 61 to 64) in temperature. So it looks like it's begun to ferment again.

I will keep everyone updated on this as it progresses...

[Charles S.]

One other thing I've found is that try to keep your fermenter glycol jackets from coming on early in fermentation. These yeasts are top fermenters and are very sensitive and remember that a lot of these yeasts were developed in open fermenter situations. I just knocked out a 20.5 trippel with the LaChouffe strain at 64 f and let the fermenter rise naturally to 71 or so. Brewed last Thursday and its at 6.0 now (open fermenter).