Getting Rid Of Acetaldehyde

[sinkas]

Hi all,
does anyone have any thoughts on how to get rid of Acetaldehyde from a force carbonated, belgian strong ale?
I have a full keg of it, and its nearly undrinkable. The flavour profile beneath the green apple is excellent, but the green apple just wont relent....

My thoughts:

1) reduce presure, and add a active yeast culture to the keg and see what happens?
2) totally decarbonate and then bulk prime and see what happens
2a) Send to fellow brewer to put through their water purification system.
3) use keg as water cannon against neighbours new labradoodle?

I have asked around, but not even the pro brewers here seem to have any ideas.

Anyone?

 

[kabooby]

I read somewhere that this should disipate with cold conditioning. Has the beer been cold conditioned? If so how long?

Kabooby

 

[kirem]

SO2 will bind it up.

 

[chovain]

According to Palmer (chapter 22.2), it should go away with time. He says that if you were to catch it in the fermenter, then you can clean it up by leaving it on the yeast longer, rousing the yeast for a bit, or conditioning at a higher temperature.

I reckon you should try bringing the temperature up for a few days, and see if that helps you. If that doesn't fix it, maybe you can repitch and recondition at a slightly elevated temperature in the hope the new yeast cleans it up.

 

[Thirsty Boy]

SO2 will bind it up.

Nice... any clues on ways to get the SO2 into the beer? Perhaps just a pinch or two of sodium or potassium met into the keg. Would you then need to leave the keg open to let any excess sulphur waft away? Would you need to let the compound formed by the SO2 and the Acetaldehyde fall out and then rack away from it?
or would it stay in solution as a flavour neutral?

Too many questions. Sorry

Thirsty

 

[mika]

Bit about it in this Month's BYO mag. Apparently can be caused by overpitching (by a huge amount), underarating, fermenting too warm or separating the beer from the yeast too soon. They simply recommend leaving it on the yeast cake for a few more days at the upper end of the temperature range for the yeast (which kinda goes against the warm fermenting argument ?) and it should clear up.
If it's in a keg...bummer...maybe just add a fairly neutral yeast, US-05 ? and leave it to chew for a couple of days.

 

[kirem]

Nice... any clues on ways to get the SO2 into the beer? Perhaps just a pinch or two of sodium or potassium met into the keg. Would you then need to leave the keg open to let any excess sulphur waft away? Would you need to let the compound formed by the SO2 and the Acetaldehyde fall out and then rack away from it?
or would it stay in solution as a flavour neutral?

Too many questions. Sorry

Thirsty

PMS.
I would pour a glass add a pinch see if it does what you want and then treat a keg. If you do it at the correct or near correct rate there shouldn't be any 'excess' sulphur to 'waft' away.

Not sure off the top of my head if it remains in solution or not.

 

[Hargie]

....patience is the only answer now....put it at the back of the fridge and pretend its completely rooted....then in a month or two reward yourself...

 

[Hargie]

....and i would not add anymore yeast or anything else you may just end up with a whole lot more grief than you've got now....


...I'm drinking a Schwartzbier right now that a month ago was Granny Smith City....it was already fined, filtered and carbonated before i detected it....so i left it in the fridge , no hasty decisions and now is scrubbed right out of the beer....it's getting judged this weekend at the ACT Champs and i guess i'll find out....i'll post the results if interested...

 

[mfdes]

In my experience leaving the beer on the yeast for a while after fermentation appears finished is always a good policy and does mop up acetaldehyde, diacetyl, and other by-products.
Once it's been kegged or bottled, however, I'd say it's patience or nothing...

MFS.

 

[ausdb]

Hi all,
does anyone have any thoughts on how to get rid of Acetaldehyde from a force carbonated, belgian strong ale?
I have a full keg of it, and its nearly undrinkable. The flavour profile beneath the green apple is excellent, but the green apple just wont relent....

My thoughts:

1) reduce presure, and add a active yeast culture to the keg and see what happens?
2) totally decarbonate and then bulk prime and see what happens
2a) Send to fellow brewer to put through their water purification system.
3) use keg as water cannon against neighbours new labradoodle?

I have asked around, but not even the pro brewers here seem to have any ideas.

Anyone?

Have you ran that by Randall? he touched on it during the talk he gave at WCB but I can't remember it :-(

 

[sinkas]

He doesnt reply to pm's

 

[Trev]

At the risk of straying slightly off topic...

There's lots of good advice given above about methods of hopefully decreasing the Acetaldehyde but maybe the question should also be asked about how it got there in the first place.

Are you happy that the yeast was in good health and you pitched sufficient quantity?

Was the wort well aerated?

Did you leave it long enough in the fermenter for the yeast to finish the job?

Trev

 

[sinkas]

Hi there,
Yes the yeast is probably to blame, or moreso the brewer punishing the yeast, after they had already succefully fermented a pale aale and a 8.5% Triple, maybe its was too much for them.......
The beer sat on the yeast for over 8 weeks, 4 of them at room temperature post cessation of fermentation.

To be honest I'm not likely to drink a keg of big belgian until next winter, so I think I will add some fresh yeast, and see what happens.

This topic does sem to highlight a definite weakpoint in the knowledge base.

 

[mika]

Your just ahead of your time Case....just like with that SaisonWeizen thingo <_<

 

[Andyd]

They simply recommend leaving it on the yeast cake for a few more days at the upper end of the temperature range for the yeast (which kinda goes against the warm fermenting argument ?) and it should clear up.

My understanding is that in the last stages of fermentation, the yeast are just cleaning up some of the crap that gets generated earlier on, so the raise in temperature has little or no effect on the production of esters etc.

Andy

 

[OneEye]

I've been having some problems with Acetaldehyde lately. My last 3 brews have been an apple cidery mess. My fermentation is Temp controlled, I always use an appropriate yeast starter (via mr.malty calcs) and I've been leaving the beers in primary for around 12-14 days. Should I be leaving it on the cake longer? Could it be an infection rather than a yeast by-product?

 

[mattyra]

It is possible that it is an infection. Give all of your equipment a good clean. I used bleach a little while ago when i detected an infection. I left the fermenter and equipment in a bleach solution for 24 hours. After that I rinsed out thoroughly (you will need to otherwise the bleach can add flavours to your beer) and haven't had the issue since. I also use starsan as a no rinse sanitiser.

I also had a problem with Acetaldehyde at one point and how I solved it was to use less simple sugars. More malts and less dextrose.

 

[OneEye]

Yeah I have my kettle and fermenters soaking in PBW now. I don't use and simple sugars, like dextrose, in my beers. AG beers here.

 

[mika]

Tell us more about your yeast handling. Acetaldehyde is mostly about poor yeast health/performance.