Why do I get mould growing on my wine once I have added the sugar and yeast?!


Question: If it is mold, it probably can be treated and salvaged. But if it is "flowers of wine," it may very well have eaten up most if not all of the alcohol in the wines "Flowers of wine" are usually white or nearly so and will not grow if the wine is over 10.5% alcohol. So, if the wines were at 12% alcohol, the chances are that it is mold.

Carefully rack the wine into a sterilized secondary, being careful not to transfer any of the mold. Dissolve two crushed Campden tablets per gallon and one teaspoon of lemon juice per gallon in a cup of the wine. Add this to the wine, top up and refit the airlock (after sterilizing it and changing the water inside it). Let the wine sit a day or two and then draw off a sample and taste it. If it tastes all right, it probably is, but only a microbiological assay of the mold can guarantee you of this. You have to make the decision to drink the wine yourself.

The only way that mold can grow on wine is for the mold spore to be introduced into the primary or secondary fermentation vessel. Always sterilize your primaries and secondaries with an appropriate metabisulfite solution, allowing at least a two-minute surface contact of the solution with the equipment.

You also need to sterilize your siphon hoses really well, as they are difficult to dry inside after use and molds can infect them easily. After use, wash them thoroughly and let drip drain until the outer surfaces are completely dry. Then use a hair drier to blow hot air through the hose until all moisture inside has evaporated. Then coil the hose up and place it in a gallon-size ZipLoc bag until needed again. At that time, fill a large bowl with sterilizing solution and place the coiled hose in it, turning it until it fills up with the solution. Leave it in there until you need it, but in any case not less than two minutes. Then drain the solution out of it and use it at once.

Primary fermentation should always take place in a covered primary. I have several primaries of varying sizes. These are washed after use, dried, and placed in ZipLoc bags until needed. Then they are soaked in sterilizing solution for 3-5 minutes, wrung out thoroughly, and placed over the primaries still moist.

Secondary fermentation should always take place under an airlock, and the liquid in the airlock should be 10% metabisulfite solution. I have had several people write and ask about making "balloon wine" or making wine without any "fancy" equipment. I don't like to talk about "balloon wine" because it is inviting trouble, and there is nothing "fancy" about a $1 airlock or $5 hydrometer. If you can't afford those two things, you shouldn't be making wine.

Alcohol is a wonderful preservative. Always make your wine 12% or higher in alcohol content by volume. Even then, there are microbes that can attack the wine or live in it -- especially sweetened wines -- so sterilize everything and minimize air contact.

Lastly, adding sulfur to the wine itself will make it that much more difficult for microbes to gain a foothold. Each time a wine is racked it should be dosed with one crushed Campden tablet per gallon of wine dissolved in a cup of the wine and stirred in well. This procedure is not written into any of the recipes, but rather is stated elsewhere. Be sure to sterilize the dowel or rod used to stir the wine.

If you follow these procedures, you should not experience a repeat of this problem.


Answers: If it is mold, it probably can be treated and salvaged. But if it is "flowers of wine," it may very well have eaten up most if not all of the alcohol in the wines "Flowers of wine" are usually white or nearly so and will not grow if the wine is over 10.5% alcohol. So, if the wines were at 12% alcohol, the chances are that it is mold.

Carefully rack the wine into a sterilized secondary, being careful not to transfer any of the mold. Dissolve two crushed Campden tablets per gallon and one teaspoon of lemon juice per gallon in a cup of the wine. Add this to the wine, top up and refit the airlock (after sterilizing it and changing the water inside it). Let the wine sit a day or two and then draw off a sample and taste it. If it tastes all right, it probably is, but only a microbiological assay of the mold can guarantee you of this. You have to make the decision to drink the wine yourself.

The only way that mold can grow on wine is for the mold spore to be introduced into the primary or secondary fermentation vessel. Always sterilize your primaries and secondaries with an appropriate metabisulfite solution, allowing at least a two-minute surface contact of the solution with the equipment.

You also need to sterilize your siphon hoses really well, as they are difficult to dry inside after use and molds can infect them easily. After use, wash them thoroughly and let drip drain until the outer surfaces are completely dry. Then use a hair drier to blow hot air through the hose until all moisture inside has evaporated. Then coil the hose up and place it in a gallon-size ZipLoc bag until needed again. At that time, fill a large bowl with sterilizing solution and place the coiled hose in it, turning it until it fills up with the solution. Leave it in there until you need it, but in any case not less than two minutes. Then drain the solution out of it and use it at once.

Primary fermentation should always take place in a covered primary. I have several primaries of varying sizes. These are washed after use, dried, and placed in ZipLoc bags until needed. Then they are soaked in sterilizing solution for 3-5 minutes, wrung out thoroughly, and placed over the primaries still moist.

Secondary fermentation should always take place under an airlock, and the liquid in the airlock should be 10% metabisulfite solution. I have had several people write and ask about making "balloon wine" or making wine without any "fancy" equipment. I don't like to talk about "balloon wine" because it is inviting trouble, and there is nothing "fancy" about a $1 airlock or $5 hydrometer. If you can't afford those two things, you shouldn't be making wine.

Alcohol is a wonderful preservative. Always make your wine 12% or higher in alcohol content by volume. Even then, there are microbes that can attack the wine or live in it -- especially sweetened wines -- so sterilize everything and minimize air contact.

Lastly, adding sulfur to the wine itself will make it that much more difficult for microbes to gain a foothold. Each time a wine is racked it should be dosed with one crushed Campden tablet per gallon of wine dissolved in a cup of the wine and stirred in well. This procedure is not written into any of the recipes, but rather is stated elsewhere. Be sure to sterilize the dowel or rod used to stir the wine.

If you follow these procedures, you should not experience a repeat of this problem.

That's the yeast. It's supposed to do that.

Sugar provides food for the mold.

Yeast is not mold. The sugar is supposed to be there to provide food for the yeast. As the yeast grows it releases alcohol and carbon dioxide as waste products. But the sugar can provide food for any mold which might have existed in the grapes (or other fruit) used to make the wine.

It has probably over fermented. Try keeping it at an ideal temperature between 70-80F

I heard it's what happens to the fruit as the fruit goes off. I think it's supposed to happen though. Try typing it in google for more info that's what I'd do.

My brother used to make homemade wine like this- he would put all of the ingredients in a bottle, then place the mouth of a balloon over the top of the bottle. The balloon would inflate while the wine was fermenting, then it would deflate. That is when it is done. I don't know how you are making your wine, but this worked for him every time, with no mold. It did take a while (maybe two weeks, but not positive). He put it in a cool corner of the house and never touched it during this process. The glass one gallon jug he used had a small mouth, and he filled it almost to the top. Hope this helps.

thats just what happens

If it is actually mold growing on your wine, then you didn't sanitize everything well. However, I agree with the first post, that is yeast colonies that float on the surface. It looks like mold, because just like mold, yeast is a fungus. If the "mold" looks like a thin layer of white dust across the surface, or is big blue/black/white fuzzy colonies, then it is mold. If it looks like tan to light brown bubbling scum, then it's yeast. When you add yeast to the wine and sugar mix, the yeast will start growing and forming colonies like what you are talking about. If this is happening right after you add the yeast, then it is definitely the yeast, because it takes longer for mold to grow on wine.

Make sure to use campden tablets or potassium metabisulphate when making your wine to prevent infections.

because your a bad speller...

don't worry, it's just grandma.





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