? regarding SG & alcohol

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cb_Sadie

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I have made a Blackberry Merlot. The starting SG was 1.052. When I stabilizing & clearing the SG was 0.996. Now it is time to bottle and the SG is 1.020. So what would my alcohol level be in the wine? How do you figure this?
 
1.052-(0.996)=.056 x 136.4=7.63 ABV
Starting SG(1.052) minusEnding SG(0.096)= 0.056 times factor (136.4)= resulting ABV= 7.6367
 
You dont count what you added after fermentation was done since it didnt ferment again although the addition of that probably brought the abv down a very little bit.
 
Thanks Appleman. I knew there was a way to figure it but I was not sure. That wine sure has a low ABV. Guess I should of add some sugar. I just followed the kit.
 
appleman said:
1.052-(0.996)=.056 x 136.4=7.63 ABV
Starting SG(1.052) minusEnding SG(0.096)= 0.056 times factor (136.4)= resulting ABV= 7.6367


Now I'm confused. While back when lurking I wrote the formula down from several similar post as /.00736 that would come out as X 135.9.
 
There are dozens of ways of figuring ABV out there, some better or easier than others, but they all are apt to be off a bit. The number you have gives a very close result to this one I used as supplied previously by Wade.
 
I would really love to know if there is a very accurate equation or if all of the info out there is just giving us a way of winging it, um, Peter Z, are you out there?
smiley4.gif
 
ASAI said:
appleman said:
1.052-(0.996)=.056 x 136.4=7.63 ABV
Starting SG(1.052) minusEnding SG(0.096)= 0.056 times factor (136.4)= resulting ABV= 7.6367


Now I'm confused. While back when lurking I wrote the formula down from several similar post as /.00736 that would come out as X 135.9.

ASAI,

(beginning SG-Final SG) / 0.00736 = % ABV [Final gravity before back sweetening or F-pack]

that is the formula I use. Its the first one I learned so it kind of stuck to my mind.
 
Wade, I am here. There is no absolute way to calculate ABV out to 5 decimal places accurately. Why? Because the yeast are changing more than sugar to alcohol. Those changes, like eating nutrient to grow, also affect SG, so any calculation we do based on SG is an approximation.


I'm sure there is a way to analyze the must for actual sugar content and then analyze the finished wine for residual sugar (before back sweetening) and calculate the exact ABV, but it would be expensive and hardly worth the effort.


Know what I use? I use the potential alcohol table that came with my hydrometer. Close enough for my needs.
 
So PeterZ,

what you're saying is its not rocket science
smiley36.gif


I just want to know about how much I am getting. It doesn't have to be precise.
 
Noted this AM that Applemans original post is now X136.4. I could have swore when I originally posted my questions it had X131.?. That caused about .3% difference in the 2 calculations. I would not have questioned 135.9 vs: 136.4.

Did you edit Appleman, or did I just not pay attention, AGAIN?



Thanks for the final matter of fact PeterZ, and for Applemans post of the automatic calculator.
 
Table Wine in the US is anywhere between 11 and 14% legally- no better numbers needed. In Europe it is between 8 and 14%. Is a couple 10ths of a percent going to matter much? If you want to list the ABV on the label you are even given 1.5% ABV deviation so you could call it 12% and 13.5% would be allowed without question even if someone wanted to check it.


And yes ASAI I did change it. I had used Wade's number. I verified it and corrected it later-right down to changing the quoted posts. When I am incorrect I like to change things if I am aware I made an error.
 
appleman said:
And yes ASAI I did change it. I had used Wade's number. I verified it and corrected it later-right down to changing the quoted posts. When I am incorrect I like to change things if I am aware I made an error.


Not to mention the fun of messing with my troubled mind!
smiley2.gif
 

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