Unusual white crust during secondary

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Sep 30, 2016
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Greetings all.

I just went to check up on a wild blackcurrant/blueberry wine that went into the secondary about one week ago, and I observed a white crust on the surface of the wine inside the carboy. To me this is strange, as the wine is still undergoing pretty consistent fermentation (a bubble per four seconds in the airlock). It went into the secondary after 5 days in the open primary, and was hit with sulfites in the beginning. I'm having a difficult time believing it is contaminated, especially during this stage in the fermentation (it's quite early, no?). Does anyone have experience with contamination during the first week of the secondary?

Attached are some photos

Thanks guys,




I am guessing you transfered a bit early and that is just the fermenting yeast cap that we usually try and punch down during the early ferment. With it in an open fermenter with a lot of headspace, I would just stir it down. In the carboy with not much headspace, if you stir it you might be in for the ole wine volcano. Get it foaming and it will probably come out the mouth of the carboy. And welcome to the forum. Arne.
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Second what Arne said, I just finished a blueberry and ended up with a little more than normal solids going into my carboy from the press. I had similar foamy deposits and proteins that formed around the neck. When fermentation was completed, I racked again with KMS and had absolutely no issues.

Your observation is correct, it's pretty hard for an oxygen loving bacteria to thrive in the CO2 producing environment you have in there at present.........
Good to hear. I just pushed down the cap last night and it has not foamed over.. All is well!

Thanks guys!
I had something like that on a kit with lots of fruit in it. I feel it was pectin - after several racks it went away.

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