Alcohol Potential

[scumbuster]

As I checked my 5 gallon carboy this morning I was looking at where the SG: was and again thought about the scale on the side for alcohol content. It is scaled from 1.000 up. But that doesn't account for alcohol production below SG 1.000. Is this because if you ferment below 1.000 it really doesn't change much in alcohol content? Is there a reason the scale for alcohol stops at 1.000 and SG goes to .990?

 

[Yooper]

As I checked my 5 gallon carboy this morning I was looking at where the SG: was and again thought about the scale on the side for alcohol content. It is scaled from 1.000 up. But that doesn't account for alcohol production below SG 1.000. Is this because if you ferment below 1.000 it really doesn't change much in alcohol content? Is there a reason the scale for alcohol stops at 1.000 and SG goes to .990?

The scale is "potential alcohol" and it's a beginning reading. That means at 1.050, if it were to ferment fully, the wine would have about 8% ABV. If the SG reads 1.000, the potential alcohol would be about 1.3%. Of course, if it was .990, there would be no sugar, so no potential alcohol at all.

It's not really an alcohol meter at all- it's a reading of potential alcohol in a sugar solution.

 

[jensmith]

As I checked my 5 gallon carboy this morning I was looking at where the SG: was and again thought about the scale on the side for alcohol content. It is scaled from 1.000 up. But that doesn't account for alcohol production below SG 1.000. Is this because if you ferment below 1.000 it really doesn't change much in alcohol content? Is there a reason the scale for alcohol stops at 1.000 and SG goes to .990?

I add in any alcohol below 1.000. My hydrometer has lines below that point. Just no potentel alcohol listed. Each .010 points is a wisker over 1%abv. So if my wine ferments to .992 I add 1% abv to the potential alcahol of the starting sg. This may not be correct practice but it works for me. My freind owns a winery and he tested several of my wines abv content. My numbers matched his. Which considering how often I round my numbers off was serprising

Not all wines will ferment much below 1.000. Its easy enough to add any "extra" abv, but would be anoying to subtract it!

The 1.000 is the sg of water. Most juices are made up mostly of water and sugers, with small amounts of other stuff. This is why the starting sg is 1.090. When you ferment the juice dry all the sugers are gone and you "should" be back to the sg of water, 1.000. The hydrometer is a weight, and density measurment thingy. Alcohol is thiner and lighter then water, so when all the suger has been converted the hydometer should set below 1.000.
It's not a straight answer to your question, but its as close as I can get




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[fuelish]

I can honestly say I've never even looked at the "potential alcohol" scale......have always just grabbed an original gravity (@60 degrees F), a final gravity (@60 degrees F) and just done the math - well, now, I just plug the numbers into any number of online abv calculators out there...I typically use http://www.gotmead.com/2014-04-16-20-10-09/mead-calculator.html , since I make mostly meads and variations...it's great if you need to account for fruit and other fermentable additions