Seriously stuck fermentation of Belgian Quad

[McG]

Could use some advice from anybody that's faced a bad stuck ferment.

We brewed a Belgian Quad back at the end of August. It was a 10 bbl batch with 550 kg of malt mashed at 148F and 15 gallons/85 kg of the D2 candi syrup.
OG was 22.3 P.

It was pitched at 68F with 4th generation BS87 Trappist High Gravity yeast (i.e. Wyeast 3787, the Westmalle strain). Fermentation took off nicely and we allowed the temp to ramp up to 82 F. But after a week or two the temp started to drop and activity slowed and stalled, while the gravity remained at 10.5 P. It is ridiculously sweet, with enough sugar left to create a session beer still.

We tried rousing the yeast to no avail. We then tried pitching a lager yeast we had handy, which was fed a little the day before to try to get it active. It did nothing. I have also pulled small samples from the tank and added some properly hydrated Nottingham dry yeast, and again have had no success.

Now, the cause of all this was probably poor yeast health after already fermenting a strong Tripel and Belgian IPA, as well as chronic overpitching and less than optimized yeast collecting procedures (sitting under hydrostatic pressure after fermentation for a while). We're addressing those issues for future batches. But I still really need to save this batch if it's possible. If anyone has any ideas on how to do that, please let me know, especially if you've dealt with the problem of a bad stuck ferment in a big beer. We can't seem to get this beer to do anything.

We're planning to try top-cropping some of our house yeast (the Fuller's strain) from another one of our beers at high kraeusen, when it is at its healthiest and most vigorous. If that doesn't work, we're about to have to either dump it or try to blend it with another batch somehow.

Please chime in if you have any ideas on how to save this batch. It's the most expensive batch we've ever brewed.

[Scott M]

I'm assuming alcohol at about 7% by volume. I'd run some off into a smaller FV say 5 gallons, raise the temperature to 68 degrees and pitch a pack of Wyeast 1388, 1450 or 1762 or vile of White Labs WLP 550 or 099 that has been started in a 10P starter wort for 3 days on a stir plate. If it doesn't go, there is more wrong than tired yeast.

You could also just throw in some Champagne yeast and let it go. It is a specialty beer so as long as you can get the sweetness out of it, you should be OK. You will just have to give it some obscure name and serve it as a one time brew.

Good luck!

[dberg]

Yeah, your best bet is to try to krausen it with 20% of a beer a high krausen (48 hours or so works pretty well). Good luck!

[jbrew55]

convertase

last resort...convertase

[brewmaster 2011]

try connecting a o2 stone to the racking arm and blowing some gas throught to re oxygenate and it will also helb get the yeast back in to suspension.

[froptus]

I would also try re-oxygenating it. I've had success with this technique in the past. Also try oxygenating and pitching with a healthy dose of your house ale yeast strain. Good luck.

[McG]

Anyone out there actually have experience with convertase? I know in the homebrew world this brings up the dreaded Beano discussion, but I'd be curious to hear anyone that's had success.

Basically my goal is simply to lower the sweetness to an acceptable threshold where we can sell the beer.

I know everybody always mentions the champagne yeast option, but has anyone actually used that successfully? Wine yeasts lack the ability to digest maltotriose and the other complex barley sugars, and I suspect this would still leave the gravity quite high. Plus I doubt it would actually take unless already actively fermenting-- at this point I don't think just pitching yeast of any kind is going to get things going, since the beast of Nottingham fell. It might work if we can get an active yeast going first.

[McG]

Yeah, your best bet is to try to krausen it with 20% of a beer a high krausen (48 hours or so works pretty well). Good luck!

Any suggestions on how to accomplish that practically speaking? How do we get that 20% from one vessel to the other? I assume we're wanting mostly the top kraeusen layer. The opening on our 10 bbl fermenter vessels is probably about 2 ft wide. Enough room to get in and do something, but are we talking scooping it up in buckets or what? We have never tried top-cropping before.

[Scott M]

If you are wanting to perform the recovery for the full batch or dump the entire batch, adding a beer in high krausen is probably your best bet.

Convertase is essentially Alpha Amylase, I have done this as a home brewer and it leaves the beer thin and without body; not what you want in a Belgian Quad.

I would start your selected yeast in a 10.0 P, highly oxygenated wort of approximately 1 bbl in your 10 bbl fermenter and transfer your Belgian Quad onto it.

[hophead82]

Please do not oxygenate your beer whatever you do. This will oxidize your beer for obvious reasons. Do use CO2 to rouse your yeast back into suspension. Then make a starter in another tank with a wort from a different batch similar in profile. Transfer beer into wort pitch and cross fingers. Convertase will also not work as the enzymes need to be present in the wort before fermentation. Enzymes do no discriminate and may eat your yeast leading to undesirable dead yeast flavors. Just my two cents from making big boy beers before. Take it as you will.

[jfulton]

Enzymes do no discriminate and may eat your yeast leading to undesirable dead yeast flavors.

Enzymes just eat everything!? Not really, first off they don't "eat" they are catalysts to specific biological reactions. They will not "eat the yeast." That being said, I would only add enzymes as an extreme last resort.

I very much agree with adding another high krausen beer at 10-20% to kick start this thing. Try to have the receiving beer near the temp of the fermenting beer for best results. I had a similar problem one time when trying a new Belgian strain the lab procured and it took forever to finally finish it out. I tried my house ale strain, nada. Finally, lowered it to the temp of a high krausen lager and transferred about 10% into the stalled beer and it slowly finished to a reasonable level.

Needless to say, it's easy to hate this beer as the brewer. Keeping you up an night, thinking I might have to dump my first batch, etc... I called it Chupacabra - Goat sucker - because i detested it. Don't get me wrong, it was very drinkable, but the whole ordeal left me bitter. Customers ended up loving Chupacabra. "Brew it again, it's great!!!"

FAT CHANCE! Even if I wanted to...

[McG]

I very much agree with adding another high krausen beer at 10-20% to kick start this thing. Try to have the receiving beer near the temp of the fermenting beer for best results. I had a similar problem one time when trying a new Belgian strain the lab procured and it took forever to finally finish it out. I tried my house ale strain, nada. Finally, lowered it to the temp of a high krausen lager and transferred about 10% into the stalled beer and it slowly finished to a reasonable level.

When you transferred the high kraeusen lager, did you simply pump it over through the racking arm? Is it just a matter of getting 10% of the volume of an actively fermenting beer into the new tank? Or should I be trying to capture some of the kraeusen itself? Obviously with your lager yeast you're not talking about a lot of foam to be top cropping, but I thought we might want to be capturing some of it from our London ESB ale strain.

I popped the lid off one of our fermenters and took a look and there's some nice froth within arm's reach. So I could get in there and try to scoop it up in bucketfuls, or I suppose I could sanitize inside and out of a hose and rig it up to our pump and dip it in there like a straw. Still could use some practical suggestions on how to actually top crop unless it doesn't really matter and any portion of the fermenting beer would do.

[jfulton]

During high krausen there are abundant healthy cells within the entire volume of the beer, so just transfer over from the racking arm or bottom valve. Also, if possible, krausen with a beer that won't totally skew the intended character of the lagging beer; but it will obviously change somewhat. Though this could lead to the creation of an interesting beer! Like I said before though, if people love the outcome and demand more you'll be left scratching your head thinking of how it can be duplicated!

[jfulton]

This may be overtly profound, but McG, are you confusing the verb krausen with the noun krausen? It's kinda confusing, but to krausen a beer is the addition of fermenting beer to another beer that has finished fermenting, for the end result of the vigorous healthy fermenting cells to clean up green beer flavors faster, shortening aging time and giving the opportunity to naturally carbonate also. The krausen of the beer, as you know, is the head on it during active fermentation.

[McG]

Yeah I realized that I've been misusing the verb kraeusen. I've been confusing it with top cropping. My initial idea was to attempt top cropping some of the kraeusen from our big Scottish Ale for the Quad. But now I understand that kraeusening doesn't require top cropping, which makes the whole endeavor much more manageable. Thanks for clearing up the confusion. I hope this can get things going again. The flavor profile of the Scottish and the Quad should be similar enough that a 10 or 15% addition shouldn't really alter things much. If this works, it will be a real save.

Thanks!