Fixing up Fusel Alcohol in the fermenter

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Patrick_BCB

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I think I got some bad advice and pitched the last three brews around 28-30 degrees centigrade prior to putting in the fridge to ferment at 18 degrees.
Doing AG BIAB IPAs with a SG of around 1.067 ish each, and one week apart. The first one with BRY-97 and two and three with US-05.

So they all have that hot persistant fusel flavour. Which I believe is due to the early alcohol produced by the yeast in the warm wort.

The ones that finished fermenting bottomed out at 1.03 FG, the third only went down 2 days ago. Can I save this? I was thinking of throwing more yeast at it while it is at 18 degrees....

From what I read some long time conditioning may help the two batches that have finished fermenting so was planning to cellar them in the fridge at 10 degrees and taste test them every couple of weeks.

Any suggestions?
 
How fast did the wort cool from 28 to 18?

If it was within 8-12 hours it is likely not the problem.
I pitch warm often. Only have vodka taste out of the fermenter when young / green. Give it a few weeks gassed in the keg fridge and you will be describing it as 'warming'.
Pitch enough yeast? 1.067 is no small task.

Cheers,
D80
 
I don't think much of anything will have been produced while the temp was dropping form 28 to 18.

I am more concerned about a FG of 1030.

How much yeast did you use for a 1067 SG?
 
Thanks for the responses.

Wort was put in the fridge straight after pitching so would have cooled way before 8 hours.

Only doing small batches so a 1/3 of an 11.5 g sachet that was rehydrated as per the manufacturer's instructions. But yes attenuation has stopped for the batch that i put down a week ago. Attempted to rouse the yeast this morning after I tasted it - so will check gravity again tomorrow.

My initial thought was to throw more yeast at it - is that a valid approach?
 
I think you would have killed most of the yeast, the surviving yeast will throw plenty of off flavours if brewed hot, and no it is something you cant fix post ferment.
In effect massive under pitch, yeast under stress = pretty bad beer
Best advice I can give you is to not take any more advice from whoever told you to add your yeast at 30oC, they don't know enough to be giving advice.
Mark
 
Might be a long shot but I had some success with Belle Saison pulling a phoenix from the fire once.

Cant hurt.

RM
 
Give it to people you don't want to ever ask you for some beers again, then sup away smirking to yourself on better made beers
 
Yob said:
Give it to people you don't want to ever ask you for some beers again, then sup away smirking to yourself on better made beers
I go the other way, I drink all my bad batches myself as a lesson not to do it again! Glutton for punishment I know.
 
I'm all for learning this lesson the hard way, just not sure which bit stuffed up.

For the next few brews I'll make sure pitching temp is somewhat nearer to 18, but I'll be doing the same big IPA and using the same yeast in the same temperature controlled fridge. So it will be interesting to see what the outcome is.
I may bump the amount of yeast I pitch.

Being a newbie I am trying to experience and learn as much as I can, so stuffing things up once and awhile is invaluable experience.
 
Patrick_BCB said:
I'm all for learning this lesson the hard way, just not sure which bit stuffed up. *** You pitched too little yeast.

I may bump the amount of yeast I pitch. *** this will work and improve the beer.
With regard to the pitching temp. There is a big difference between pitching yeast in at 30 degrees, and actually fermenting at 30 degrees.
If you get to fermenting temps quickly after pitching, I would be looking elsewhere for the culprit.

Sounds like lesson learnt and you are on your way. :beerbang:
Cheers,
D80
 
Update.

I am continuing with the 30 degree pitch temp but have adjusted how my thermocouples connect to the fermenters.

I'd like to put them directly into the wort but don't have a method of sealing properly so I have continued to put them on the side but am insulating on the outside with multiple layers of bubble wrap. Previously I just used duct tape only.
Saw an immediate 3 degree drop after using the bubble wrap as an insulator and so assume I've been fermenting everything at least 3 degrees higher than I was measuring...

Wait and see how the next batch turns out.
 
You mean the outside of the fermenter is 3oC hotter than the inside? Seriously
That just doesn't sound likely or even possible unless it's very hot outside and your temp controller is very badly setup.
Mark
 
No, I think it was reading the fridge air temp rather than the fermenter temp, well at least maybe an average of the two.
 
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