Name this infection.

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LunarRaven

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So I’m quite new. My wine was made with apples, oranges, and white grapes. After it sat for close to a month when a sort of ‘slime’ formed on the top. It was like little bubbles of slime sitting on top. So I carefully racked. This has been sitting for probably close to 8 weeks and now there is this. Upon doing some research I realized I have way too much headspace. But what can be done now ? And this new film appears to look different than the first time.
 
I name it Luis.

But seriously, the "slime" is called a pellicle. It indicates the presence of wild microbes and oxygen. It's totally normally for wild fermentations. We cannot determine which wild microbe(s) may be present without microbiological testing.

How does it taste?
It's possibly fine to proceed to packaging, or you should transfer it to a smaller vessel.

Sulfite can help control the wild microbes, especially if you don't plan to naturally carbonate. However, wild microbes can also sometimes be helpful, so inhibiting them isn't necessarily required.

Welcome to HBT!
 
I name it Luis.

But seriously, the "slime" is called a pellicle. It indicates the presence of wild microbes and oxygen. It's totally normally for wild fermentations. We cannot determine which wild microbe(s) may be present without microbiological testing.

How does it taste?
It's possibly fine to proceed to packaging, or you should transfer it to a smaller vessel.

Sulfite can help control the wild microbes, especially if you don't plan to naturally carbonate. However, wild microbes can also sometimes be helpful, so inhibiting them isn't necessarily required.

Welcome to HBT!
Luis I like it.
But yeah, from what I was reading it seems it was a pellicle at first. But this looks a bit different. And I’m a bit confused as to if pellicle is good or bad ? I seem to see conflicting things about it being a protective layer or an infection.

I haven’t tasted it yet but I will here in a minute.
I do plan on transferring to a glass carboy since I’ve got 2 1/2 gallons of wine sitting in a 5 gal bucket.
 
Well I tasted it. I’m not sure what contaminated wine is supposed to taste like but this just tastes young and a bit gassy.
 
It is definitely a pellicle.

Luis is neither "good" nor "bad", he's just there to tell you that wild microbes and oxygen are both present.
Think of it like the bubbling/foam after you add your yeast. It just indicates that the yeast are active and fermenting; there's nothing good or bad about it.

A pellicle can be helpful in the sense that it prevents oxygen in the headspace from getting into the wine, to some degree. However it's better not to have so much headspace.

Contaminated wines aren't "supposed" to taste like anything in particular. Typically in wine wild microbes aren't a big problem.

Happy to answer questions or try to explain differently if this doesn't make sense. Wild microbes are my specialty. :)
 
It is definitely a pellicle.

Luis is neither "good" nor "bad", he's just there to tell you that wild microbes and oxygen are both present.
Think of it like the bubbling/foam after you add your yeast. It just indicates that the yeast are active and fermenting; there's nothing good or bad about it.

A pellicle can be helpful in the sense that it prevents oxygen in the headspace from getting into the wine, to some degree. However it's better not to have so much headspace.

Contaminated wines aren't "supposed" to taste like anything in particular. Typically in wine wild microbes aren't a big problem.

Happy to answer questions or try to explain differently if this doesn't make sense. Wild microbes are my specialty. :)
Thank you for your explanation you’ve been very helpful. I’ve almost tossed the batch a couple of times.
 
If something tastes or smells bad then toss it but if it doesn't "scunner" you (and that's a good Scottish word that means that it turns your stomach when you see, smell or taste something) then it's probably OK. Hydrogen sulfide (a smell of rotten eggs or sewer gas does not mean that the wine is bad only that the yeast have produced hydrogen sulfide because of stress (or because they are high H2S producers) To remove H2S you might whip air into the carboy or transfer (rack) the wine through copper scrubbing wool. To remove surface mold you might siphon the wine and simply leave the top inch or so behind.
 
is kahm yeast not considered a mold? And does all mold have tendrils that go deep into the body of a liquid or simply stay on the surface? What about a once common problem - ropiness in a wine is that a fungal infection or bacterial?
 
is kahm yeast not considered a mold?
Yeast and mold are different things (and both are fungi).

A pellicle (AKA "kahm" a colloquial term which literally means "skin") is formed by yeast and/or bacteria. It is visually distinct from mold growth and because mold is potentially allergenic and toxic it's good to know the difference.
does all mold have tendrils that go deep into the body of a liquid or simply stay on the surface?
Mold is filamentous by definition, so generally, yes, all mold can form "tendrils" to some extent. However since we're dealing with liquid it doesn't really matter since contact with mold could spread the possible allergens and toxins/carcinogens throughout.
What about a once common problem - ropiness in a wine is that a fungal infection or bacterial?
Ropiness (high viscosity) is the product of exopolysaccharides (EPS). It's commonly attributed to the growth of Pediococcus (bacteria), but other organisms can also produce EPS, so I wouldn't say Pedio is the only possibly cause. Brettanomyces (yeast) is capable of breaking down the EPS, removing the ropy problem.

:mug:
 

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