Actual ABV way over potential ABV

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HankRearden

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I made a couple of small batches where I shot for an ABV of 13.5 using the chart that came with my hydrometer - about 1.105 starting SG
They ended at .994 which resulted in 14.5% ABV according to some online calculators and the wine tasted very strong
So I'm thinking that the chart is based on the idea that you would cut off fermentation at SG = 1.0 ?

Is that correct with most of these potential ABV charts?
 
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Johnd

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I made a couple of small batches where I shot for an ABV of 13.5 using the chart that came with my hydrometer - about 1.105 SG
They ended at .994 which was about 14.5 according to some online calculators and the wine tasted very strong
So I'm thinking that the chart is based on the idea that you would cut off fermentation at SG = 1.0 ?

Is that correct with most of these potential ABV charts?
I don't use ABV charts, I use fermcalc (photo attached). You can see the results for a starting SG of 1.105 and final SG of 1.00. This is an accurate tool, and I use it for everything related to making my wine calculations.

IMG_0729.jpg
 

Julie

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Take your starting sg Minus your final reading and multiply by 131. This will give you your ABV.
 

HankRearden

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Take your starting sg Minus your final reading and multiply by 131. This will give you your ABV.
I understand, but it seems that it would be difficult to estimate the final ABV unless you can predict the final SG at which fermentation will end on it's own.
Or cut off fermentation at a chosen SG.
 

jgmann67

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I made a couple of small batches where I shot for an ABV of 13.5 using the chart that came with my hydrometer - about 1.105 starting SG
They ended at .994 which resulted in 14.5% ABV according to some online calculators and the wine tasted very strong
So I'm thinking that the chart is based on the idea that you would cut off fermentation at SG = 1.0 ?

Is that correct with most of these potential ABV charts?

To answer your questions: Yes, for whatever reason your chart is based on a 1.000 cutoff. And, no, I don't believe that's the case for other charts. But, others here have correctly pointed out that fermentation won't stop at 1.000 unless you stop it with kmeta; and you should consider doing the math or getting an ABV calculator.

"Dry" wine - meaning it will ferment no more - will end up around 0.990, not 1.000. And, as this lesson has taught, you'll get a bit more alcohol than originally anticipated. There are worse lessons in winemaking than a higher ABV. If you're trying to predict your potential, use a projected FG of 0.994 or something closer to "dry" and know that your ABV will likely be there +/- 0.5%.
 
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Julie

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I understand, but it seems that it would be difficult to estimate the final ABV unless you can predict the final SG at which fermentation will end on it's own.
Or cut off fermentation at a chosen SG.
trying to cut off fermentation is nothing less than a crap shoot. Unless you sterile filter there is no guarantee you can stop fermentation at a certain point. Have your must at a certain starting gravity will get you to the desired ABV.
 

Johnd

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To answer your questions: Yes, for whatever reason your chart is based on a 1.000 cutoff.
Jim, it doesn't seem to me that his chart is based upon 1.000, that was the point of the fermcalc snapshot I posted, based on 1.105 start and 1.000 finish, ABV of 13.5% was already out the door.

@HankRearden, can you post a photo of the chart you are using?
 

jgmann67

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Jim, it doesn't seem to me that his chart is based upon 1.000, that was the point of the fermcalc snapshot I posted, based on 1.105 start and 1.000 finish, ABV of 13.5% was already out the door.



@HankRearden, can you post a photo of the chart you are using?

Seeing the actual chart would help. I plugged the numbers in to the Ap I have and it landed at 13.8% using his start at 1.105 and projected end of 1.000. So, I figured, ehhh... close enough.
 

salcoco

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the fascination on actual ABV is interesting. I doubt that any person could detect the difference between 13.8 and 14.3. Even the federal government allows a +/- of 1.5% error on commercial winery's declaration of ABV.
 

HankRearden

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the fascination on actual ABV is interesting. I doubt that any person could detect the difference between 13.8 and 14.3. Even the federal government allows a +/- of 1.5% error on commercial winery's declaration of ABV.
It may be acidity that gives the illusion of more alcohol. But wife and I really feel as though it tastes closer to a port.

These are just test runs with Welch's so I really want to learn how to fine tune it and someday transfer my knowledge to other batches with different juices.

BTW thanks everyone for the good advice.

Now it seems clear that I should ditch the chart and assume a final SG at < 1.0, then pick my starting SG that would yield a desired ABV and add sugar until I reach my starting SG... But it also seems that doing so might yield a different ending SG than I might expect, like the two variables are tied together (starting and ending SG).
Curious - I suspect that there is a chapitalization calculator into which I can plug my current SG, volume and desired ABV (not desired starting SG) and it would tell me starting SG, ending SG, and how much sugar to add. Does such a calculator exist?
 

Johnd

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It may be acidity that gives the illusion of more alcohol. But wife and I really feel as though it tastes closer to a port.

These are just test runs with Welch's so I really want to learn how to fine tune it and someday transfer my knowledge to other batches with different juices.

BTW thanks everyone for the good advice.

Now it seems clear that I should ditch the chart and assume a final SG at < 1.0, then pick my starting SG that would yield a desired ABV and add sugar until I reach my starting SG... But it also seems that doing so might yield a different ending SG than I might expect, like the two variables are tied together (starting and ending SG).
Curious - I suspect that there is a chapitalization calculator into which I can plug my current SG, volume and desired ABV (not desired starting SG) and it would tell me starting SG, ending SG, and how much sugar to add. Does such a calculator exist?
Yes, and it does that and a lot more. Search for "fermcalc" and download the version that corresponds to your platform (I use the version for my iPad, there's one for PC's, Android, etc).
 

Scooter68

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Suggest that you shoot for a range for the ABV. Taking into account what the ABV will be if your fermentation stops at any of the logical spots of:
.990
.995
1.000
or even 1.005.

That way you way you will have an idea of what to expect. Over time and many batches I bet you will become pretty good at understanding what you will have in the end WHEN you start. I've only had one surprise but that was at the extreme end. I was shooting for a Black Current for a dessert wine with an ABV of 17-18% as a goal (Starting at 1.128 and assuming an end SG of .990). My yeast was capable of that but the fermentation stopped cold on it's own at 1.005 and remained at that point until I bottled it with no change in the SG. SO I still had a high ABV (16.7%) but I didn't have to backsweeten since it stopped with a residual sweetness that met my desires. Today my wife call that wine batch "Potent" with a strong flavor, and enough Alcohol so that a half-glass of that wine is all you need. (By the way I made that from a can of Black Currant concentrate and is great)
 

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