Acetaldehyde problems

[slackerlack]

I continue to have acetaldehyde flavors and aroma in my beers. I am trying to figure out where I am getting this off flavor from. I thought I was racking the beer off the yeast to early, so I let it sit longer and still had the problem. My last two batches, I let sit for 3.5 weeks in the primary before kegging. I didn't taste or smell it when I kegged. I am not filtering my beers but I do cold crash. Would keeping the kegs at 45 degrees make the yeast start back up and cause off flavors?

 

[CadillacAndy]

I continue to have acetaldehyde flavors and aroma in my beers. I am trying to figure out where I am getting this off flavor from. I thought I was racking the beer off the yeast to early, so I let it sit longer and still had the problem. My last two batches, I let sit for 3.5 weeks in the primary before kegging. I didn't taste or smell it when I kegged. I am not filtering my beers but I do cold crash. Would keeping the kegs at 45 degrees make the yeast start back up and cause off flavors?

What yeast strain? What temperature? If liquid yeast - are you making a starter? If dry yeast - are you rehydrating first? What is your pitch rate and what is the starting gravity of the beer?

The two places I'd start would be yeast health and pitching rates. If the yeast are dying off or flocculating out before fermentation is done, that could be your problem.

 

[slackerlack]

Using Wyeast 1056 with a 2L starter on the first beer. Then washed the yeast and pitched for the second beer. Then washed that one and pitched into the other two that I brewed at the same time.

Ferment temp on all 4 beers was 67 degrees.

Different starting gravity for each beer, basically went up for each beer. Starting from 1.054 and going up to 1.066.

Fermentation is completing and the beer tasted fine when I racked it into the keg. It even tasted good on tap for the first week or so, then it started smell and taste like green apples. I always bleed any oxygen out of the keg when I keg my beers.

 

[CadillacAndy]

Using Wyeast 1056 with a 2L starter on the first beer. Then washed the yeast and pitched for the second beer. Then washed that one and pitched into the other two that I brewed at the same time.

Ferment temp on all 4 beers was 67 degrees.

Different starting gravity for each beer, basically went up for each beer. Starting from 1.054 and going up to 1.066.

Fermentation is completing and the beer tasted fine when I racked it into the keg. It even tasted good on tap for the first week or so, then it started smell and taste like green apples. I always bleed any oxygen out of the keg when I keg my beers.

Have you had anyone else taste the beer? I thought I had a similar situation a couple of weeks ago, but several other people didn't get acetaldehyde.

If it's tasting fine when you keg it and starts to go south after a bit of time in the keg, I'd think more of a contamination issue.

 

[slackerlack]

Yes, I have had other people taste it and they agreed. It's pretty strong.

Not sure where the contamination could be coming from. Can you get a contamination in your CO2 lines?

 

[CadillacAndy]

Not sure where the contamination could be coming from. Can you get a contamination in your CO2 lines?

That's probably one of the things I'd replace last if I couldn't get it figured out.

How are you getting your beer from the carboy/bucket to the keg?

How were you storing the yeast in between batches? Pitching directly on the cake of the previous batch? What was the temp when you added the yeast? How long was the lag time between pitching and fermentation? Did the wort sit without yeast in it for any period of time (possibly waiting for it to acclimated to room temp)?

 

[slackerlack]

I was using an auto-siphon and a tube connected. I just got a new siphon and tube to isolate that out of the issue.

I was not storing the yeast since I was going directly from the carboy, to my mason jars during the wash, and into the new wort. All within a few hours. All sanitized and I "washed" the yeast properly. Pitched with yeast at 67 and wort at 67. Lag time was only a few hours since it was washed fresh yeast and ready to go. It took a few hours to get the wort from 90+ degrees, water in Texas is hot, down to 67 degrees.

 

[CadillacAndy]

It sounds like it might be a contamination issue. I'd guess a wild yeast got in some how. I'd probably sanitize everything and try another batch.

The same thing happened to me. I had a dirty keg jumper and contaminated 4 kegs.