Stuck fermentation

The Green Man

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'Help, I have a stuck fermentation...aargghhhh' probably not the rarest question on here...but bear with me.
The Chocoffee Stout:
<iframe width="100%" height="500px" src="https://www.brewersfriend.com/homebrew/recipe/embed/1080605" frameborder="0"></iframe>
Went from 1.056 to 1.021 over two weeks. Target was 1.016. Warmed it to 20c, swirled gently, three days later no movement...so I had a sachet of champagne yeast so I thought 'that will help mop up the remaining sugar'...Of course after I had added it, I read that champagne yeast also has a 'kill factor' which basically kills other yeast...great. So quite possibly I have made the situation worse.
Next bright idea was to add 50g of table sugar diluted in boiled water to encourage the yeasties back to life (the solution cooled to 30c before adding).
My question to you guys is whether I bottle or not (assuming that there is no further movement)?
My current thinking is to stir the fermentor to mix the existing sugar solution through the wort and then bottle with no addition of priming sugar.
Obviously, this is imprecise but inadvertently, the champagne yeast kill factor might help to stop bottle bombs (might also stop some good bottle conditioning too, but that ship has sailed).
The remaining original sugar which wasn't fermented (which isn't that much, surely) and the 50g addition I will treat as my priming sugar...if any priming actually takes place now is in the lap of the beer gods.
Do you think my thinking is unwise, plain dangerous or reasonable?
 
I'm no expert but here it goes. If the wine yeast did not bring down your gravity, then the additional sugar still remains in solution. The wild card here is the amount of yeast remaining to condition further. There may not be healthy yeast to clean up the sugar in the bottle.
 
I'm no expert but here it goes. If the wine yeast did not bring down your gravity, then the additional sugar still remains in solution. The wild card here is the amount of yeast remaining to condition further. There may not be healthy yeast to clean up the sugar in the bottle.
Thanks Frankenbrewer. I hear you. I had no idea Champagne / sparkling wine yeast were so harmful to the ale yeast.
Another one to learn from. This brew has been a good learning experience. The last sample tasted pretty good, but that was before the 50g sugar addition. I will also add coffee beans and ground coffee 12 hrs before bottling so there should be enough flavour in it. A little sweetness won't be a bad thing with all the cocoa, coffee and vanilla essence in there...just the exploding bottles I am a touch concerned about...
 
First, a stalled fermentation is fine as long as the beer isn't sweet or sweeter than you intended. It may not be "stalled", it may have just finished all or most available fermentable sugars. I'm not a big fan of adding additional yeast, but it's not a bad thing either.

I would first taste it. If you like it, leave it set for a couple of days and let the yeast that's already active finish the sugar you added. Then bottle it with the proper amount of priming sugar. If you really want to make sure you won't have bottle bombs, let the beer set for another 2 weeks, some yeasts do come back to start again. The additional time won't hurt the beer. Adding yeast to beer will hinder the yeast because of the already presence of alcohol and lack of sugars. The yeast gets dumped into an environment with no food.
 
First, a stalled fermentation is fine as long as the beer isn't sweet or sweeter than you intended. It may not be "stalled", it may have just finished all or most available fermentable sugars. I'm not a big fan of adding additional yeast, but it's not a bad thing either.

I would first taste it. If you like it, leave it set for a couple of days and let the yeast that's already active finish the sugar you added. Then bottle it with the proper amount of priming sugar. If you really want to make sure you won't have bottle bombs, let the beer set for another 2 weeks, some yeasts do come back to start again. The additional time won't hurt the beer. Adding yeast to beer will hinder the yeast because of the already presence of alcohol and lack of sugars. The yeast gets dumped into an environment with no food.
Thanks HighVoltageMan! I have read that Champagne yeast is used to mop up left over sugars after high abv fermentations, but never read about the 'kill factor' until after I dumped it all in (5g not 11g like our ale yeast packets) I kind of assumed that this yeast will be ok in the presence of alcohol. It's the side effects I am more worried about. Done now, so no escaping that.
I will be tasting it tomorrow which will be four days after the new yeast addition and three after the sugar addition. Will be interesting to see the reading. If it's about the same, I will assume that the champagne yeast has converted the new sugar. If it is less than my last reading, I will assume that it has munched down on some of the left over original sugar...if there was any (as you rightly pointed out).
Just never had a beer finish above 1.020 before. Seemed too high to be finished to my amateur eyes.
 
'Help, I have a stuck fermentation...aargghhhh' probably not the rarest question on here...but bear with me.
The Chocoffee Stout:
<iframe width="100%" height="500px" src="https://www.brewersfriend.com/homebrew/recipe/embed/1080605" frameborder="0"></iframe>
Went from 1.056 to 1.021 over two weeks. Target was 1.016. Warmed it to 20c, swirled gently, three days later no movement...so I had a sachet of champagne yeast so I thought 'that will help mop up the remaining sugar'...Of course after I had added it, I read that champagne yeast also has a 'kill factor' which basically kills other yeast...great. So quite possibly I have made the situation worse.
Next bright idea was to add 50g of table sugar diluted in boiled water to encourage the yeasties back to life (the solution cooled to 30c before adding).
My question to you guys is whether I bottle or not (assuming that there is no further movement)?
My current thinking is to stir the fermentor to mix the existing sugar solution through the wort and then bottle with no addition of priming sugar.
Obviously, this is imprecise but inadvertently, the champagne yeast kill factor might help to stop bottle bombs (might also stop some good bottle conditioning too, but that ship has sailed).
The remaining original sugar which wasn't fermented (which isn't that much, surely) and the 50g addition I will treat as my priming sugar...if any priming actually takes place now is in the lap of the beer gods.
Do you think my thinking is unwise, plain dangerous or reasonable?
I think you simply have a high FG and the beer is done. In the future here's how to tell: Take a sample, you can use either a refractometer or hydrometer, every day for three days. If there's no change in gravity, it's done. I've even tried this with the infamous 3724 yeast, the Saison yeast that likes to stall at 1.03. Every day there was change, if only less than a point.

Here's the thing: Once the yeast quits, it's hard to get it to start back up. It quit for a reason: Either it ran out of sugar, the most common, or it ran out of viable cells. Any other outcome and the yeast will continue to work! Some highly flocculant yeasts can squeeze another point or three if you swirl them up into solution again but generally the yeast quits because it's done.

My advice: Let the sugar you added ferment out. It will do so pretty quickly because you didn't add much. Then prime and bottle normally. As I said, when the yeast is done, it's done. Priming just adds more sugar so those yeast cells still in suspension can process it, again a good indication that the fermentation was done before you added the sugar.

Good luck with it.
 
I think you simply have a high FG and the beer is done. In the future here's how to tell: Take a sample, you can use either a refractometer or hydrometer, every day for three days. If there's no change in gravity, it's done. I've even tried this with the infamous 3724 yeast, the Saison yeast that likes to stall at 1.03. Every day there was change, if only less than a point.

Here's the thing: Once the yeast quits, it's hard to get it to start back up. It quit for a reason: Either it ran out of sugar, the most common, or it ran out of viable cells. Any other outcome and the yeast will continue to work! Some highly flocculant yeasts can squeeze another point or three if you swirl them up into solution again but generally the yeast quits because it's done.

My advice: Let the sugar you added ferment out. It will do so pretty quickly because you didn't add much. Then prime and bottle normally. As I said, when the yeast is done, it's done. Priming just adds more sugar so those yeast cells still in suspension can process it, again a good indication that the fermentation was done before you added the sugar.

Good luck with it.

Cheers Nosybear. Sounds all logical and good.
I forgot to mention that we had a cold snap and despite having a temp controller and a heating element, the ferm vessel was basically in a cardboard box. Would a drop to say 16c be enough for the yeast to drop out? Or, do you think the temp bump and swirl would have been enough to rouse them if they did drop out due to a temp drop?
It was this drop in temp together with the quite high FG that was behind my suspicions that the fermentation had become stuck. Should have added that in the original post...doh!
 
And...curiosity got the better of me. Just took a gravity reading and it is a smidgen lower than when I added the sugar solution. Now sitting at 1.020-1.0205.
Sample doesn't taste at all sweet. Quite dry if anything which seems a bit odd to me with an FG as high as this.
Could it be the cocoa powder has contributed to this in some way? I added 250g with 5mins left to go in the boil.
If I were a betting man I would say it is done though. But I will give it another couple of days before allowing myself to think about bottling.
 
And...curiosity got the better of me. Just took a gravity reading and it is a smidgen lower than when I added the sugar solution. Now sitting at 1.020-1.0205.
Sample doesn't taste at all sweet. Quite dry if anything which seems a bit odd to me with an FG as high as this.
Could it be the cocoa powder has contributed to this in some way? I added 250g with 5mins left to go in the boil.
If I were a betting man I would say it is done though. But I will give it another couple of days before allowing myself to think about bottling.
The potential to drop out depends on the yeast you were using - some English yeasts give up if the temperature drops too much! Keep monitoring it, when it doesn't change for three days straight, bottle it!
 
I had a dopplebock at 10C for 2 weeks and it stopped quite high, when I brought it inside and let it warm up the yeast started right back up.
 
'Help, I have a stuck fermentation...aargghhhh' probably not the rarest question on here...but bear with me.
The Chocoffee Stout:
<iframe width="100%" height="500px" src="https://www.brewersfriend.com/homebrew/recipe/embed/1080605" frameborder="0"></iframe>
Went from 1.056 to 1.021 over two weeks. Target was 1.016. Warmed it to 20c, swirled gently, three days later no movement...so I had a sachet of champagne yeast so I thought 'that will help mop up the remaining sugar'...Of course after I had added it, I read that champagne yeast also has a 'kill factor' which basically kills other yeast...great. So quite possibly I have made the situation worse.
Next bright idea was to add 50g of table sugar diluted in boiled water to encourage the yeasties back to life (the solution cooled to 30c before adding).
My question to you guys is whether I bottle or not (assuming that there is no further movement)?
My current thinking is to stir the fermentor to mix the existing sugar solution through the wort and then bottle with no addition of priming sugar.
Obviously, this is imprecise but inadvertently, the champagne yeast kill factor might help to stop bottle bombs (might also stop some good bottle conditioning too, but that ship has sailed).
The remaining original sugar which wasn't fermented (which isn't that much, surely) and the 50g addition I will treat as my priming sugar...if any priming actually takes place now is in the lap of the beer gods.
Do you think my thinking is unwise, plain dangerous or reasonable?
The Champers should of got things going I'm sure that stuff attenuates pretty good and has a high alcohol tolerance being a wine yeast.
Have you checked gravity again after pitching this.
Heat n swirl is my only help and if nothing
I'd go with your bottle without priming solution but I'd give it another couple of days first.
 
Ben, if he gives it another couple of days, that 50g of sugar he mixed in will be CO2 and alcohol. I'd reprime.
 
The Champers should of got things going I'm sure that stuff attenuates pretty good and has a high alcohol tolerance being a wine yeast.
Have you checked gravity again after pitching this.
Heat n swirl is my only help and if nothing
I'd go with your bottle without priming solution but I'd give it another couple of days first.

Hey TrialBen. Thanks for the post. I reckon that champers yeast has munched through all the extra sugar and maybe a bit more as it is reading a touch less than before I added the sugar. Gone from 1.021 (before sugar addition) to 1.0205... roughly. Hydrometer readings aren't exact, so that is my best guess. I'll give it a few more days and take another reading. If it moves a lot I will leave it until it settles.
I think Nosybear is on the money, all that extra sugar has already gone into CO2 and alcohol :D . Will definitely need the priming sugar I reckon. Never had a beer finish at 1.020 or above before. This is what freaked me out. This wasn't a high gravity beer either.
Love this brewing business. Always more to learn.
Thanks for all the input guys. Much appreciated.
 

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