Has this happened to anyone before.

[ktm250]

So right after Christmas I made an IPA. Everything went well and tasted good in the initial brewing process. Fermentation went well, nice and strong and I hit my final gravity right on.

Before I put the beer in the bottles to condition it tasted great. Now everything is done and I am getting random diacetyl in bottles. Not every bottle, so far it has been about a third of the bottles with this off flavor. What could cause some bottles to have this flavor and not others?

The only thing I can think of is that we had a major ice storm two days after I put the bottles up to condition and I lost power for two days. Temps fell to 30 degrees in the house. Could that have messed up the fermentation in the bottle and produced this random off flavor?

 

[theredben]

Dropping temperatures like that would not have caused diacetyl. Diacetyl is a by-product of fermentation and would be produced in the fermener. Are you sure it is diacetyl? What yeast did you use?

 

[wonderbread23]

Pediococcus can throw some diacetyl. Perhaps some localized bottle infections? Also, diacetyl often doesn't become evident until the beer has had a chance to warm up. It might taste fine at bottling, but once they warm up and condition, the diacetyl makes itself present.

 

[ktm250]

I dont know. I had the bottles in the oven at 350 degrees for two hours immediately prior to bottling. That should have taken care of bottle infections I thought. I was wondering if the small amount of fermentation that takes place to carbonate the beer could have been incomplete because of the cold temps and possibly caused diacetyl. I thought that if the entire batch had been infected by something in the fermenter then it would be all the bottles, not just about a third of them.

 

[MrMeans]

I had the same thing happen to me with my last brew. I am thinking that it was either the chemical I used to take the labels off the bottles (oxiclean, a.k.a. my wifes theory) or that a portion of my bottles got too warm at some point. My new trick is that I am going to bottle condition in a cooler filled with water and monitor the temperature to maintain a constant temperature during conditioning and see what it does. Try it out and see what your results are. Good Luck!

 

[millsware]

Warning if you condition in a water bath: don't submerge the caps as they will rust. Not enough to rust away, but will leave a ring around the mouth of the bottle.

 

[breez7]

Also, dry heat takes a lot longer to sanitize then wet heat or sanitizer. 350* in the oven would prob take the bottles 2-3 hrs to sanitize. Buy some star san.

 

[theredben]

It would not be the bottle conditioning itself that caused the diacetyl. wonderbread23 had a good point about bacterial populations. Oven sterilizing only works until you open the door. How long have they been in the bottle for?

 

[superjunior]

Pediococcus can throw some diacetyl. Perhaps some localized bottle infections? .

that was my first thought

 

[MrMeans]

Thanks for the tip millsware.