Need help with stalled fermentation (tricky)

[bigcirjust]

I’m taking over winemaking this year for my father for the first time (medical issues-memory), and having an issue with what seems like a stalled fermentation.

We’re making Alicante from grapes, crushed and initially 19 Brix, added sugar and brought up to 22 Brix, then fermentation started. Everything was going along smoothly for about a week and then it stalled at 7 Brix for 2 days, and the must cap collapsed with all solids falling below and seeds floating. We had some cold nights and I’m thinking that probably contributed.

The tricky part is my father decided to press and barrel it today. So we have a full 50 gallon barrel along with 3 full 5-gallon carboys. I’ve attached fermentation locks and, not surprisingly, no bubbling yet after a few hours.

My father is from Italy and makes wine completely Old World style, never using any added yeast. I’m thinking maybe it could use some at this point? Very tricky as everything is now in containers obviously, in the cellar. It tastes pretty good right now, but not full-bodied at what I’m calculating to be about 9% alcohol. If primary fermentation went to completion I was estimating it would be 12-13%. I know there is usually the secondary fermentation, but I don’t know how extensive that would be with 7 Brix.

Any advice or guidance would be appreciated, thanks in advance. Cheers.

 

[G259]

The first thing I thought was "add more yeast', but then I was thinking that acidity might be an issue? Amateur, but I'm throwing it out there anyway!

 

[salcoco]

some thoughts start a yeast starter with EC1118. once fermenting well, take a portion about a cup from one of the carboys add to the yeast starter. once fermenting add two cups once fermenting add four cups continue doubling the amount each time fermentation begins. hopefully you now have 5 gallons fermenting. now the tricky part use this five gallon in part into the barrel I would remove some wine from the barrel to give it some fermenting room also place some in the other 5 gallon carboys. another choice is to step through the same method on the other carboys and then go for the barrel with about 5 gallons of fermenting must. good luck

 

[sour_grapes]

How are you measuring the Brix? Hydrometer or refractometer?

 

[bigcirjust]

How are you measuring the Brix? Hydrometer or refractometer?

Refractometer

 

[bigcirjust]

some thoughts start a yeast starter with EC1118. once fermenting well, take a portion about a cup from one of the carboys add to the yeast starter. once fermenting add two cups once fermenting add four cups continue doubling the amount each time fermentation begins. hopefully you now have 5 gallons fermenting. now the tricky part use this five gallon in part into the barrel I would remove some wine from the barrel to give it some fermenting room also place some in the other 5 gallon carboys. another choice is to step through the same method on the other carboys and then go for the barrel with about 5 gallons of fermenting must. good luck

This sounds like a good approach, thanks. I have a wine supply store I can drive to that has EC-1118 in 5 gram increments it looks like. Any thoughts on how much to use exactly?

 

[sour_grapes]

Refractometer

Good news! Your fermentation is probably finished.

You cannot take a straight reading from a refractometer after fermentation has started. Alcohol has a different index of refraction than water, and skews the results. There are ways to correct for this, but easiest to just use a hydrometer. A fully finished fermentation shows up on a refractometer's nominal Brix scale near where yours is now.

See: - ValleyVintner Main Page

 

[salcoco]

agree with @sourgrapes. measure with hydrometer I believe your wine is finished. no need to try with a yeast starter. refractometer is good if using spreadsheet for correction. always good policy to check end fermentation with a hydrometer.

 

[bigcirjust]

Good news! Your fermentation is probably finished.

You cannot take a straight reading from a refractometer after fermentation has started. Alcohol has a different index of refraction than water, and skews the results. There are ways to correct for this, but easiest to just use a hydrometer. A fully finished fermentation shows up on a refractometer's nominal Brix scale near where yours is now.

See: - ValleyVintner Main Page

Ok great, thanks for the advice. I just purchased one and it should arrive tomorrow, I will measure and go from there before I do anything else. I’m a little skeptical that this is the case, as the wine has some slight sweetness to it, and doesn’t taste very alcoholic, but we will see.

 

[bigcirjust]

agree with @sourgrapes. measure with hydrometer I believe your wine is finished. no need to try with a yeast starter. refractometer is good if using spreadsheet for correction. always good policy to check end fermentation with a hydrometer.

Thanks, will do.

 

[bigcirjust]

Good news! Your fermentation is probably finished.

You cannot take a straight reading from a refractometer after fermentation has started. Alcohol has a different index of refraction than water, and skews the results. There are ways to correct for this, but easiest to just use a hydrometer. A fully finished fermentation shows up on a refractometer's nominal Brix scale near where yours is now.

See: - ValleyVintner Main Page

Good news! Your fermentation is probably finished.

You cannot take a straight reading from a refractometer after fermentation has started. Alcohol has a different index of refraction than water, and skews the results. There are ways to correct for this, but easiest to just use a hydrometer. A fully finished fermentation shows up on a refractometer's nominal Brix scale near where yours is now.

See: - ValleyVintner Main Page

Good news! Your fermentation is probably finished.

You cannot take a straight reading from a refractometer after fermentation has started. Alcohol has a different index of refraction than water, and skews the results. There are ways to correct for this, but easiest to just use a hydrometer. A fully finished fermentation shows up on a refractometer's nominal Brix scale near where yours is now.

See: - ValleyVintner Main Page

**UPDATE** - I measured with a hydrometer yesterday and the specific gravity was 0.994, so it appears you are correct and there is no more/minimal residual sugar. Thanks again!