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Stuck Ferment?

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PostModern

Iron Wolf Brewery
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I have never had a stuck ferment before, but I'm pretty sure I've got one now. Here's the history of the brew and what I've tried so far.

I have a weizen brewing away and it's going fine. Anyway, the next day I put on a partial mash pale ale. Here's the recipe:

Grain:
1Kg Munich
250g CaraMunich III
80g Crystal (80)

Exract:
1.8Kg Light DME

Hops:
18g Northern Brewer 60 mins
12g Tettnanger 10 mins
12g Czech Saaz 5 mins

Etc:
1/2 tsp Whitelabs Yeast Nutrient 5 mins
S-05 SafAle yeast.

OG was 1.046. Lousy efficiency because of my small mash tun and even smaller boil pot. I did check that the mash was complete with the iodine test and it was fine.

Anyway, I rehydrated the yeast and it was frothing and multiplying happily when I pitched. After 2 days I noticed the airlock had stopped bubbling. Not wanting to use the bubbling as a scientific instrument, I took another gravity reading. It was 1.020. Fine, there was fermentation. 24 hours later (yesterday) it still read 1.020, so I checked it again today and yep 1.020.

So I thought, rather than pitch another whole pack of SafAle (my last one :( ) I thought I'd try and give it a kick with the K-97 SafWheat that was bubbling in the Wiezen. So I took a (sterile) glassful of the fermenting wiezen and pitched that into the pale ale. When the top was off the pale's pail, I noticed some brownish stuff floating in the froth on the top of the beer. I wasn't too preturbed by this at the time, but now I wonder if it's an infection. The brew smells fine, tastes like partially fermented beer (I always taste my hydrometer samples) but the gravity is still not moving! AArrrgghh. Funny thing is that there is some carbonation in the samples. If it agitate the fermenter, I get airlock activity but it dies after a few mins. I assume swirling it just releases some of the dissolved CO2.

What to do? Give it a few more days and recheck the gravity? Give it a hearty "rousing" with the brew spoon? Shake rattle and roll? Bottle? (/jk)

EDIT: Don't know if it's relevant, but it might be the key - when I was putting the brew on, I noticed that the gravity was low. Initially I had only 1.5kg in the boil but when I saw a 1.040 beer at 22 litres, I got another 300g of DME and just dissolved it in boiling water then added to the fermenter.
 

GMK

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PoMo

This is my advice.
Rack the beer to a secondary - dry hop and leave for two weeks.
This should kick it into gear again.

Note:
I have bottled beers this high before.
If you cant get the fg down below 1020 - bottle with no priming sugar.
Over time it will ferment out and gas up.

Hope this helps.
 

PostModern

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Cheers Ken,
It was down to 1.019 this morning (meniscus between 020 and 018). I noticed one bubble too. I think it might have been the k-97 kicking in.

I ended up "rousing" it this arvo too. Gave it a big paddling to see if it'd wake up. It's bubbling now but I think it might just be the dissolved CO2 coming out. If it's still bubbling this evening, I think it might be back alive. The yeast cake was quite firm. I think it may have just flocced to early - I had it at room temp when active fermentation started and noticed it rise to 23C, so I moved the fermenter into the bathroom where it dropped to 21C overnight. Maybe I sent the yeast into shock with a sudden temp change? Anyway, I'll keep you posted. Will probably rack it Sunday anyway.
 

PostModern

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Strange brew. The rousing only kept it bubbling for a few hours on Friday.

Yesterday, as the mercury started climbing and the fermenter went up to 24C, it started again. It's been bubbling for 24 hours now. I might rack it in a day or so, once I'm sure fermentation is almost over and there is viable yeast in suspension.

Damn thing.
 

deebee

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Jovail Monk did a great post on stuck ferments a few months back. See if you can find it.

Amongst his suggestions was to make up a big starter with wort from the stuck batch. Pitch at high krausen.

Like GMK says, if you are bottling it, go ahead and just severly underprime it. It will condition into something good in time.
 

PostModern

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It fermented a little further on its own on Saturday and Sunday. By Sunday evening it had stopped again. I haven't taken another gravity reading yet, but suspect it'd still be a little high. I'm going to call this batch "Flemish Signalman's Ale" because it stops and starts... <_<

I racked it and dry hopped with a GMK standard measure Half-Handful ;) of Saaz pellets. I think I'll just let it take it's time and see what comes out. My sanitation is pretty good, so I'm not afraid of infection or anything.
 

PostModern

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OMG!
This brew ended up stopping at 1.016/7. I primed it with just a little less DME that I normally use, as I suspect the high FG was from the Munich and Cara having not enough enzymes to convert all the starches.

Anway, it tastes beautiful now 20 days in the bottle. One of the nicest batches I've brewed, in fact.

Thanks for your reassurance, Ken. This batch turned out great. I'm looking forward to sharing it with family at Xmas :)
 

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