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Author Topic: Occassional diacetyl problem  (Read 1016 times)

Offline cfleisher

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Occassional diacetyl problem
« on: February 26, 2011, 11:51:15 am »
I've been noticing a strong diacetyl presence in several bottles of doppelbock that I bottled about a month ago. Weird thing is that it's not every bottle. Some of them seem just fine. Is this possible, or am I just making this up? If some bottles have a diacetyl problem and others don't, what accounts for it? My sanitation methods are pretty thorough (or so I thought.)
Primary: Grapefruit IPA
Secondary: Berliner Weisse

Offline hopfenundmalz

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Re: Occassional diacetyl problem
« Reply #1 on: February 26, 2011, 12:38:42 pm »
If your beer was low in diacetyl when finished fermenting, you can get it from:
1. An infection, but you said you are on the sanitation thing.
2. Exposure to air at packaging.  O2 will oxidize the diacetyl precursor into diacetyl.  When I read that in "Yeast", I realized what happened to my Second Round Pilsner last year.  The keg was fine, and it scored high in the first round.  I got rushed bottling and did not purge the bottles with CO2, maybe was a little rough getting them filled.  I had bottled a few extra, and the one I drank after I got the scoresheets had enough diacetyl that I could pick it up, even with my medium high sensitivity to it.   Live and learn.

Jeff Rankert
AHA Lifetime Member
BJCP National
Ann Arbor Brewers Guild
Home-brewing, not just a hobby, it is a lifestyle!

Offline hopfenundmalz

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Re: Occassional diacetyl problem
« Reply #2 on: February 28, 2011, 11:13:45 am »
Jeff Rankert
AHA Lifetime Member
BJCP National
Ann Arbor Brewers Guild
Home-brewing, not just a hobby, it is a lifestyle!