Identify white stuff floating on top of the wine

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Dec 8, 2022
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My first post. Im a newbie and making my first wine:)
I was going to bottle my wine but when opening the lid I found some white stuff floating on top. Is this mycoderma bacteria?
I have made wine from grapes only and its a very small batch. (4,5 litres) in a 25 litres bucket. A couple of weeks ago I transferred from my other bucket and used coffe filter to filter out some of the lees.
I guess I introduced too much oxygen in that process and also with a lot of open space in the bucket I guess too much air made those bacterias grow? The lid has been closed all the time with a fermentation lock filled with water.

The wine smells good. I have not tasted it yet though.

Is there any good way to save the wine?

Appreciate all help, thanks:)


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The headspace did you no favors. As soon as possible rack the wine and add Kmeta. Taste it, you may be ok. What’s on the surface is not always an indicator of what the wine tastes like.

Get an appropriate size container so there is little headspace, rack while trying to avoid getting any of the white into the new container.
Hi and thanks for reply. I tried to get rid of the white on top. Then I racked it to another carbooy. I added tiny bit of sulphites. Then I ran everything through a wine filter to another carboy. At the end the wine is still very cloudy. I tasted it and it tastes very good but I feel like a lot of the alcohol is gone. It taste like a very good juice. I havent swollowed it but when I spit it out there is a lot of red particles. Its almost like its a watery but with all theses tiny red particles. I guess its ruined? Since Its actually smells and tastes good. Is it any way I can use it? Maybe fortify it? Also how do I clear it up? its kind of grainy.. Thanks again for helping
Let’s go back to square one.

What was the SG when you started fermentation? What is it now? I had assumed (incorrectly I guess) that the wine had finished fermentation. Or was nearly finished.

It should not be cloudy to the point it has particles. After filtering it (rule of thumb is to NOT filter cloudy wine) still is cloudy?
My first post. Im a newbie and making my first wine:)
I was going to bottle my wine but when opening the lid I found some white stuff floating on top. Is this mycoderma bacteria?
I have made wine from grapes only and its a very small batch. (4,5 litres) in a 25 litres bucket. A couple of weeks ago I transferred from my other bucket and used coffe filter to filter out some of the lees.
I guess I introduced too much oxygen in that process and also with a lot of open space in the bucket I guess too much air made those bacterias grow? The lid has been closed all the time with a fermentation lock filled with water.

The wine smells good. I have not tasted it yet though.

Is there any good way to save the wine?

Appreciate all help, thanks:)
put it through a coffee filter after opening
I think a little wine making 101 is in order. In the fermenting phase it's important to provide oxygen through daily stirring for the yeast to thrive, but as things progress you need to reduce and then eliminate contact with the air as much as possible. Basically, any time after the ferment is about 2/3 to 3/4 done, you should either cap it with an airtight lid or put it in a vessel like a carboy, or a gallon jug, filled up into the narrow neck to reduce surface area and cap it with an airlock. In my opinion since you're using such a large fermenting vessel for such a small amount, you would have been better of to transfer to a gallon jug when your SG was around 1.01 or so. A 25 liter bucket is too much volume for the CO2 to displace the air with a 4.5 liters of must.
There are a lot of question that come to mind from reading your post. You mention that you transferred it to a carboy. What size carboy is it, and how much headspace is there? Did you let it clear naturally, or did you add any clearing agents. How long did you let it clear for? You didn't mention degassing. Did you degas when you transferred it? I wouldn't mess with pouring it through coffee filters, but rather let the lees drop for a few weeks and rack into another vessel. Repeat until it's clear. or use sparkolloid or another clearing agent to speed up the process.


Thanks for helping:)

Ill go through every step I did so far. This is my first time winemaking. Im located in Norway and yes we have grapes but its not much.

I picked 6,4 kg grapes from my mothers garden. They were quite sweet and kinda small but tasted pretty good. Thick skinn so I guess they are wine grapes.

I have obviously done a lot of wrong in the process but to be honest I just watched this video on youtube as an inspiration.


-I was collecting the grapes October 19. and I put them on 25 litres fermenter (plastic container) I was cleaning all the grapes with water + picking out the bad stuff before getting into the fermenter. I pressed them slightly in the tank and removed all the stems.
The fermenting didnt start, just a little tilting of the water in the airlock bubler.

-Octobre 24. I put a whole pack of yeast in the mix ( I followed the instruction first blending the yeast with water)
The bubling startet the day after I believe and lasted for maybe 4-6 days.

It just took a while before I had the time to open the container again and press the grapes and throw away the grapeskins and seeds. In the meantime it started to ferment again. It took some days before the airlock bubler was stable again. I guess maybe it was a secondary fermentation?

-Novembre 13, I opened the tank for the first time and pressed the grapes. I racked it to my other fermentation 25 l plastic container. I guess first mistake . Very big headspace with only 4-5 litres of wine.I felt the wine tasted good but was a bit sparkly

-Novembre 20. I opened the tank again and did some filtering with a funnel and a grid. I got rid of a lot of lees. I tasted the wine and it tasted smoothe with kinda buttery taste like I taste in a good wine. Note: I did not use a siphon. And I transferred it back to my other 25 l plastic container , fermenter again, because it was all I had. I didnt think about the headspace.

-Novembre 24. I did open the container and did a filtering again. Again I did not use a siphone. Just pourd it through the same funnel and grid but this time I added coffe filter. I had issues that the coffe filter did clog up a lot and I used a lot of them. I think I used about an hour. The wine still tasted goos, but it was very cloudy. The coffe filted didnt seem to collect the cloudy particles much. I noticed that the wine was kind of wite ish which I felt was very strange for a red wine?

-December 8. I was going to transfer the wine to bottles. I opened it and it had a small film with the white particles as shown in the pics in the first post. So then I made a post on this forum.

-December 11. I bought a wine filted. I also bought two 5 l carboys. first I tried to get rid of the white particles with a spoon. I thinkl I got rid of at least 70% of the big white stuff. The smaller particles probably just wanished into the wine again. I transferred the wine to the 5 l carboy. I tried with a siphon but it was hard to transfer it as it was my frst time, so I messed it up and ended up transferring everything including the lees. I added sulphite ( just a super tiny bit, maybe 1/10 of a teaspoon blended in a tiny bit of room tempered water ) sealed it with a cork. Then I fixed my wine filter and started to filter from the 5 l carboy to the other 5 l carboy. I messed it up because nothing went through the filter. I added a siphone with a pump and started pumping. I got all the lees in the siphone but It went through. I think it went a way around the filter because I still have a lot of stuff at the last 5 l carboy. I did taste the wine and it tasted good, very juicy, but not sure about if the alcohol was there anymore. Maybe a little bit. The consistent was prett grose, and it felt the wine had sand in it, I did not swollow but when I spitted it out in the sink it had a lot of red particles in it.

I have an alcohol meter I purchased from ebay so my plan is to measure it the next time I open the carboy.

Ill post some photos of whats left. I spoiled a lot of wine in the last transfer.

In the carboy it looks like the wine has many layers. One or two? tiny at the top. One bigger unclear and 2 different layers at the bottom. SEE PHOTO

Also when I watched the glass I used to taste it the last time, it had white stains / legs and som white stuff in it. tiny crystals? SEE PHOTO

The strange thing is that when smelling the glass it smells really good. Like a nice perfumed wine hehe


Can I use this wine, if what can I do next? Any suggestions?

I have not spottet any of the white stuff at the top. Is it safe to taste and drink?

If I get rid of the lees, if the wine has to little alcohol after I measure it. Then itsnot usable I guess? I know there is alcohol in there but it feels like its a bit on the low side

I know I have really messed up here hehe. But my plan was to make some wine to my family for christemas that from my mothers beautiful garden.

I literally dont know anyone in Norway making wine so thats why I found this forum. I appreciate all your help. I just try to learn as I go from here, Thank you very much for helping!



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You are still really early in the fermentation process. Good news... everything looks normal. White particles, I believe are just fine lees, nothing to be concerned about.

Oct 24, you threw away the skins. Probably should have left them in longer. Skins contribute color and tannins to the wine.

Nov 13, poured, or siphoned, doesn’t really matter, but the headspace you now know is an issue. Short term, especially early in fermentation is ok, not long term.

Nov 20, used a strainer, not really a filter in winemakers speak. Filtering requires pumps etc and get to micron size particles. No damage done here by you. A lot of unnecessary work, but no damage.

Dec 8, bottling already? No! Way to early. This is where the wine should be siphoned to a carboy with as little headspace as possible. Enough so that you can get your siphon in the carboy without overflowing and spilling. Probably 1-2”, or 4cm. Add 1/4 teaspoon Kmeta to the carboy, fit with an airlock and leave alone for 3 months, or until you see appreciable sediment, which might be in another month, guessing.

The taste is good, you see legs on your glass, this is a sign of alcohol. You are definitely on the right track, again I say, no damage done. Christmas tasting? Probably way too early, perhaps in 2023. If you have any extra wine after topping off the carboy, put it in a glass jug/bottle and put in the refrigerator. You can bring this out at the 2022 Christmas to tease everyone about what they might expect next year. There is likely to be sediment, so the coffee filter might not be a bad idea.

Well done!
Finally had some time to watch the video. I wouldn’t recommend following his example.

After crushing, a hydrometer should be used to measure the specific gravity. For grapes, if appropriately ripe it should be 1.090, add sugar if it’s less than that. The fermentation bucket was a good size, lots of oxygen access. The bubbler is not needed now, just a towel to cover the bucket. Make a yeast starter a day before adding it to the juice. Add some Kmeta to the juice kill off any wild yeast, or bugs, etc that might be on the grapes.

After 24 hours, add the yeast starter by pouring it gently into the juice. Let it sit still for 12-24 hours, covered with a towel.

After the 24 hours, twice a day, push the cap of grape skins down into the juice. Stir vigorously to introduce oxygen. Measure the SG. Once it gets close to 1.020, put a lid on the bucket and an airlock. Leave it still until you notice the bubbles in the airlock gets to about 1 per minute. Then siphon to a sanitized carboy, keeping headspace to a minimum.

The bubbles in the airlock means CO2 is being generated by the yeast which protects the wine, so headspace is not an issue. When the bubble rate decreases, the CO2 is no longer being generated so headspace IS an issue.

By the way, the sparkling, or fizzy taste is the CO2 in the wine. Over long term aging it will disappear. If you absolutely have to serve it this Christmas, you will have to vigorously stir the wine to get it out of the wine. Immediately return the wine to a sanitized carboy with some Kmeta and age it until it’s clear of sediment.
Hi. Thank you very much for helping, appreciate it:)

First off, Thanks for a lot of great information. Im learning from every reply on this tread. Thanks, appreciate it:)

There will probably be a lot of newbe questions in the following read:)

“You are still really early in the fermentation process”

Hm There has been no bubles at all for a long time, and I thought the fermentation was over. Isnt fermentation just the first days/weeks when it still buubles and co2 escapes? What defines the fermentation process?

“Oct 24, you threw away the skins. Probably should have left them in longer. Skins contribute color and tannins to the wine.”

I see my explanaion was a bit unclear. But Oct 24. I just blended in the yeast. The skins was in the bucket until I pressed the grapes Nov 13. :)

So what I should do is to rack it off the sediment into another carboy right? And add the sulphite.
I think there is only 2 litres left hehe. I have been searching online to find a smaller carboy but all I can find is 5 litres. Thants what I have now but the headspace is too much.
Any suggestions what I can do? I have read about people filling ut the carboy with marbles is it a good idea?

“Add 1/4 teaspoon Kmeta to the carboy”

Wouldnt that be a lot for just 2 l of wine?

Some quick questions:

This is probably a newbie question.
I noticed when I opened one of the packages of powder there was some dust that got up in the air.
I read this “Be careful not to breath the dust in or gas that is released when dissolving in water. I’d also steer clear of sipping on any samples immediately after adding this to your wine. Give it time to bond with the oxygen.”
Maybe I stupid question but are you guys very careful when dealing with it? Im just always worried when Im dealing with chemicals and stuff like that haha
If I want to taste the wine after it is added for how long should I wait after I pour wine in the glass?

As I understand , Sulphite will be reduced when its in contact with oxygen? And dissapear ?

Amount of sulphate:

I watched a video on youtube and the guy says the correct measurement is 87 mg per liter. How important is it to match it and do I need to weigh it correctly? Is there any harm to add too much of it?

Alcohol level:

I measured the alcohol with a vinometer. Its about 10 %
I also blended the wine 50% with water. Then it was about 4,5-5.( and doubling it) So I guess its betweeen 9.5 -10 %.

This is a bit on the low side right? Will the alcohol content go up a bit, or will it stay stabel? Any ways to have the alcohol % go up? I guess its too late because if the yeast dont react I will end up with a sweeter more funky wine right??

I didnt add any sugar at all during fermentation so I guess thats why its on the low side. And I didnt know about/using a hydrometer

But is it a possibility also that the mycoderma has eaten up some of the alcohol? Or is it common that the wine will not go over 10% if no sugar is added? See photos of first post


The wine is a tiny bit acidic. Will it be smoother after 3 months in the carboy? Or is there any stuff I can add to lower it?

Thanks again for all the help, appreciate it:)


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Fermentation ends when the specific gravity, as measured with a hydrometer, gets to 1.000 (approximately). Bubbles in your airlock are not a good indicator as CO2 also produces bubbles.

Racking should be done when there is appreciable sediment in the carboy. Some use a 1-3-3 rule of thumb. Rack at 1 week after pitching, then 3 weeks later , and again 3 months later. These are guidelines, not rules. The SG should be the guide especially early in the fermentation.

Addition of Kmeta is 1/4 teaspoon for a 5 gallon carboy. Adjust as needed for different size containers. Kmeta is a strong chemical but safe if used correctly. The instructions don’t say to drink or to breathe so use judgement. So if you dose some wine you might want to wait a few weeks before drinking a bottle. I’ve drank a few glasses of leftover wine that had been dosed at bottling. I got a little upset stomach.

Kmeta will disperse over time. So for long term aging it’s recommended to add a dose every 3 months, even if you don’t rack it.

Alcohol level won’t increase unless you add more sugar and yeast. Acidity might soften over time. If it’s still acidic in a few months, additional sugar, called back sweetening, can mask the acidity.

In my opinion I think it’s really early in the process for bacteria to form on the surface of the wine. You do have way to much headspace for aging. If you can’t find smaller glass jugs, try your grocery stores, you might try 1 liter soda bottles

Thanks again for great help:) Im learning a lot:)

I have been looking for smaller carboys for the past week, but Im not able to find anything here in Norway unfortunately. There is a website in Poland that sells 2L , 2L, 3L etc. But they are all without an airlock, just a screwcap.
How important is it to get one with airlock at this time. Hasnt the bubbling stopped pretty much?

Also after the 5 L has been sitting on my bench for a week I noticed some of the white stuff is coming back. Ill attach a photo. Its probably the mycoderma that are forming again? Its at the edges and starting covering the whole surface.

Im a bit stuck now what to do.

1. Should I just order some smaller carboys without airlock from Poland, probably waiting a couple of weeks on the delivery?

2. Should I just try to get rid of the Mycoderma, Transferring everything and filter to wine bottles. Botteling? Or just put a vacu vin wine pump cap on it. Let the lees settle and re botteling? Putting it in the fridge maybe?

If Im going to add the sulphites and blend it in water first I think the wine will be much thinner. Its probably just 2 litres right now.

Im just trying to decide what to do next hopefully not spoil the wine in the meantime. It has been so much work for so little haha

PS! I actually put some wine away in a small half bottle. It has been in my fridge for a ween. It very clear and all the sediment is on the bottom. There was a couple of spots in the wine I filtered with a coffe filter. The wine tasted really good but almost like a Rose. After I drank it it left some kind of strange astringing taste in my mouth though. Maybe it was a bit too acidic. Not sure really.

Thanks again, Cheers:)


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