Author Topic: Gunk above krausen  (Read 568 times)

Offline kramerog

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Gunk above krausen
« on: April 28, 2014, 10:34:52 AM »
I was kegging this weekend when I could see I was going to fill the corny before emptying the carboy, so I ran the excess beer into another carboy containing a split of the same batch.  The level in the second carboy is below the dried gunk from the krausen.  I know the dried gunk is supposed to be harsh and bitter.  If I had filled the second carboy above the gunk what would have happened to the beer? 
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Offline brewsumore

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Re: Gunk above krausen
« Reply #1 on: April 28, 2014, 06:03:33 PM »
If you didn't open the bucket with the dried krauesen much during fermentation, and that gunk wasn't there for much more than a couple weeks, and if you racked out of the bucket very soon after beer rose above the dried krauesen, I would guess that you would have only a slight risk of infecting the beer, especially if it was racked into a keg and the keg was put in a kegerator to chill. 

The alcohol in the finished finished beer makes it less prone to infection than fermenting beer,  and if not much air from outside the sanitized bucket got to the gunk I doubt it would build a lot of bacteria quickly.  Also, if the gunk is hardened and you remove the beer from the bucket before the gunk dissolves back into the beer, again, pretty doubtful the beer that went over the level of the dried krauesen would get infected.

Offline ynotbrusum

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Re: Gunk above krausen
« Reply #2 on: April 29, 2014, 03:21:12 AM »
I have racked onto a fresh yeast cake (just after racking off the finished beer) and fermented a second batch without cleaning the fermenter and didn't experience any problems or discernible off flavors (I don't make it a practice to do this, mind you, but once I tried it, since I was stepping up from a smaller beer to a bigger beer - and it reached the first krausen ring).
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Offline kramerog

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Re: Gunk above krausen
« Reply #3 on: April 29, 2014, 07:22:41 AM »
I have racked onto a fresh yeast cake (just after racking off the finished beer) and fermented a second batch without cleaning the fermenter and didn't experience any problems or discernible off flavors (I don't make it a practice to do this, mind you, but once I tried it, since I was stepping up from a smaller beer to a bigger beer - and it reached the first krausen ring).

Good to know.  I don't plan to make it a practice to fill over the krausen ring when transferring beer between splits of the same batch, but sometimes it is expedient.  I kinda figured my concern was more theoretical than real since it can be really hard to remove the krausen ring.
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Offline tomsawyer

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Re: Gunk above krausen
« Reply #4 on: April 29, 2014, 01:03:29 PM »
Most of the "braunhefe" (there term for the dark-brown, bitter compounds that actually float at the top of the krausen) falls back into the beer unless you skim it off at high krausen.  And obviously not many people skim, so I think this is not a real issue.  The stuff forming the ring is typically denatured protein, and won't really do anything to your beer.  Denatured protein doesn't redissolve in beer, it just sits there or it might drop down to the bottom of the fermentor if it comes loose.

The one thing I have seen with the ring, is that it can develop a little mold over time if it is left above the surface of the beer.  This is not an every-time event just once in a great while.  I guess being protein and out in the air, it procvides a better perch of a mold than beer itself.  Still, I would rather harvest the yeast cake out of a fermenter, clean the fermenter and then repitch.   
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