Red dust

[Cycius]

Hello everyone. This year i harvested my little wineyard (4 winetrees, 16 kg total grapes which is good result i guess) maybe a week too early, so the sugar/acid balance was not ideal i guess so. I put smashed grapes to a bucket for 4 days and after that i pressed juice out of it. I fermented wine for 17 days in wine jugs and decided to remove sediment. Fermentation stopped, which is good or bad thing thing i don't know. And "red dust" apeared on the surface of the wine. I guess it's not a good thing, so now i am thinking for a way to solve this. I go for natural fermentatio, no yeast added. So i guess i should remove some wine from surface and add so sugar/water/yeast. I'm not sure yeat.

 

[Ohio Bob]

Hello everyone. This year i harvested my little wineyard (4 winetrees, 16 kg total grapes which is good result i guess) maybe a week too early, so the sugar/acid balance was not ideal i guess so. I put smashed grapes to a bucket for 4 days and after that i pressed juice out of it. I fermented wine for 17 days in wine jugs and decided to remove sediment. Fermentation stopped, which is good or bad thing thing i don't know. And "red dust" apeared on the surface of the wine. I guess it's not a good thing, so now i am thinking for a way to solve this. I go for natural fermentatio, no yeast added. So i guess i should remove some wine from surface and add so sugar/water/yeast. I'm not sure yeat.

It’s hard to say from the picture but it looks harmless, possibly residue from the pressing. If it’s an active fermentation, what was your SG?, then CO2 will attach to particles and float them to the surface.

 

[Rice_Guy]

Wine is a preservative, it has low pH starts with sugar and ends with alcohol. The main risk is an oxygen organism growing producing an off flavor.
We use metabisulphite to add a layer of protection against bacteria. Normally I would say pull the red dust off with a paper towel and examine it. Is it soft / mold like? Is it hard / crystal like? With mold I would then treat with 75 to 100ppm meta to reduce it. If you are organic your number one control is pasteurize the wine as 140F for 40 minutes. Other choices are sterile filtering and removing oxygen in a vacuum capping machine, ,,, but these aren’t good at home.
Red crystal material should not matter. It would likely be related to potassium bitartrate crystals from picking with high acid.

How does your wine taste?

 

[Cycius]

It’s hard to say from the picture but it looks harmless, possibly residue from the pressing. If it’s an active fermentation, what was your SG?, then CO2 will attach to particles and float them to the surface.

I tried to measure SG and it was 0.9. I removed a litle bit wine from top and added some water/sugar syrup. I let grow too much clusters on the vinetrees which is why they did not reached necesery sugar level until i had to harvest it. So next year i'm gonna leave no more 50 clusters on one vinetree.

 

[Cycius]

Wine is a preservative, it has low pH starts with sugar and ends with alcohol. The main risk is an oxygen organism growing producing an off flavor.
We use metabisulphite to add a layer of protection against bacteria. Normally I would say pull the red dust off with a paper towel and examine it. Is it soft / mold like? Is it hard / crystal like? With mold I would then treat with 75 to 100ppm meta to reduce it. If you are organic your number one control is pasteurize the wine as 140F for 40 minutes. Other choices are sterile filtering and removing oxygen in a vacuum capping machine, ,,, but these aren’t good at home.
Red crystal material should not matter. It would likely be related to potassium bitartrate crystals from picking with high acid.

How does your wine taste?

This wine taste and smells not bad at all. But it is not as good as my last year wine (from fully rippen grapes, crystal clear and matured). I tried to remove those dust with hoose but they came back. I added little of sugar/water syrup to make sure there is minimum air space. I use metabisulphite as well, so i guees it's not gonna be completely spoiled. Next year i'm gonna buy good juice press and grow no more than 50 clusters on vinetree to achieve better sugar content.

 

[Rice_Guy]

If you are adding sugar, you can restart fermentation. A similar wine is best. I always put hydrometer samples back in the carboy. Water dilutes the wine which is OK if that is all you have.

When I add sugar, I am also adding sorbate and then bottling in a day or so.

 

[Ohio Bob]

I tried to measure SG and it was 0.9.

That’s an impossible number. Did you mean 0.900 (not physically possible), 0.990, or 0.999? It’s best to report SG to 3 significant digits.