What could this be due to?

[dina_di]

I didn't know where to ask this question, so I'll ask here.
My parents and I make wine from our grapes every year, and everything has always been fine. This year, however, the wine in the bottles started to mold, and we don't know what is causing it. We added the same amount of sugar and processed the grapes as usual, and we don't know if we can fix it or pour it out. The gloves we attached to the neck of the bottle didn't even inflate, meaning there was almost no fermentation. What could this be due to?

[bilgriss]

Usually mold is suppressed by fermentation. The increasing alcohol keeps many things at bay, and the CO2 scrubs oxygen from it. You answered your question with the observation that there wasn't any significant fermentation. That means either the yeast wasn't viable, or something in the mix kept it from kicking off fermentation quickly enough. Did you use something like sodium metabisulfite, and could it have not had enough time to air off before pitching the yeast?

[dina_di]

Usually mold is suppressed by fermentation. The increasing alcohol keeps many things at bay, and the CO2 scrubs oxygen from it. You answered your question with the observation that there wasn't any significant fermentation. That means either the yeast wasn't viable, or something in the mix kept it from kicking off fermentation quickly enough. Did you use something like sodium metabisulfite, and could it have not had enough time to air off before pitching the yeast?

Everything was done in the same way as in the past. But only this year is there a problem. We followed all the “rules”. Could it depend on the grape variety or on the fruit of this year? It was quite hot. And we don`t use metabisulfite. Usually it's just natural fermentation, but this is the first time I've seen mold. Is there any chance of saving it?

[subbrew]

Get some commercial yeast and pitch. The mold is on the surface. If you can clean it off and pitch a good aggressive commercial yeast you might save it.

[Reefer1]

+1 on bilgriss comments
+1 on subbrew comments.
I make wine never had that happen though make sure you vigorously airate the must before pitching.
I would have a taste as well see if it's sweet and ok no off tastes.

[dina_di]

Get some commercial yeast and pitch. The mold is on the surface. If you can clean it off and pitch a good aggressive commercial yeast you might save it.

I'll try it, thanks for the advice

[dina_di]

+1 on bilgriss comments
+1 on subbrew comments.
I make wine never had that happen though make sure you vigorously airate the must before pitching.
I would have a taste as well see if it's sweet and ok no off tastes.

I am so upset. I don't want to throw it away. I will taste it and try to save it.

[bilgriss]

If you were totally relying on natural yeast to kick it off, the weather can have a great impact on what yeast or how much is there. Extreme heat or prolonged strong rain for instance. The main reason wine makers customarily add yeast is to get a predictable product and process. They usually can't afford for it to work 'most of the time' and wait till next year if it doesn't.

There's a very good chance if this hasn't languished for some time that simply skimming off the mold and pitching some yeast will work out!

[dina_di]

If you were totally relying on natural yeast to kick it off, the weather can have a great impact on what yeast or how much is there. Extreme heat or prolonged strong rain for instance. The main reason wine makers customarily add yeast is to get a predictable product and process. They usually can't afford for it to work 'most of the time' and wait till next year if it doesn't.

There's a very good chance if this hasn't languished for some time that simply skimming off the mold and pitching some yeast will work out!

Thank you so much!!