Actions to take for possible mycoderma

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Feb 14, 2015
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Howdy, folks. I've been searching threads, but am looking for confirmation.

I've made a few kits, but am very much a beginner. I have WE Veneto Amarone bulk aging in two 3-gal glass carboys. The wine is in the neck of the carboys, but still several inches below the top. Today (day 91 of aging), I was planning to rack both to another container and dose with K-meta.

However, little white pearls were floating in one carboy and a bit of pink scum in the other. Apologies for the miserable photo, but when I moved the carboys to a place with more light for a better photo, both substances disappeared, presumably sinking below the surface. No film is present on the carboy necks. Both carboys smell fine.

Are both of these likely to be mycoderma?

Several threads suggested removing this stuff from the surface of the wine (with a paper towel, or baster). I can try that if it resurfaces, but if it doesn't...

Does it make sense to go ahead and rack as planned and dose with, say, 1/4 tsp K-meta per 3 gallons? I can redistribute the wine so that in one 3-gal it is well up the neck, and put the remainder in smaller carboys for the same reason.

My cellar temp was mid-60s. I believe I can get everything in a kegerator that I haven't been using (doh!) to keep the wine at 55 deg from this time on.

thanks, bws

I would use a paper towel to try and soak up as much of the stuff floating on top. Then hit it really hard with some KMETA. Top up with something to get it close to a couple of inches from the neck. Then (and this is important) get a solid stopper and seal it up. Mycoderma needs air so take away that and it can't live.
I have had this. As Ibglowin said, I soaked it up with a paper towel, wiped the neck with a towel soaked in K- meta, dosed the wine with K- meta, then topped up and misted K-meta in the neck of the carboy and sealed it up. I let the wine age for another three months and It did not come back.