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MeaderBaker
02-05-2011, 10:21 AM
I measured my sugar content when I first pitched my yeast back in November.
I got a reading of 14 % potential alcohol. Which translates to 1.12 S.G.? Correct?

I have just finished measuring it again and got a reading of 0 for potential alcohol content. Which then translates to 1.0 S.G.

the guide then says 133*(SG-FG)
so, 133*(1.12-1.0) =
133*(.12) = 15.96 % alcohol
Did I do this right? Seems high

Mead: JAOM recipe off the forum * 5 gallon


Thanks for any help

kudapucat
02-05-2011, 11:24 AM
I measured my sugar content when I first pitched my yeast back in November.
I got a reading of 14 % potential alcohol. Which translates to 1.12 S.G.? Correct?

I have just finished measuring it again and got a reading of 0 for potential alcohol content. Which then translates to 1.0 S.G.

the guide then says 133*(SG-FG)
so, 133*(1.12-1.0) =
133*(.12) = 15.96 % alcohol
Did I do this right? Seems high

Mead: JAOM recipe off the forum * 5 gallon


Thanks for any help

First up, let me recommend you buy a hydrometer that ONLY has SG reading on it, ABV and available sugar readings are skewed by the amount of alcohol in a batch.
Usually meads use a factor of 135 so a 1.100 has a max potential of 13.5
Beers use a factor of 128 or something, So can skew your numbers a bit.

Next: What yeast were you using? What's its ABV tolerance? - hmm perhaps JAP suggests bread yeast, so you have NFI regarding that last q.


you've used a factor of 133, as above, I usually use 135. but close enough eh...

Your discrepancy comes in your assumption that avail able sugar: 14% translates to 1.12 yet you use 133 for your next calc.
133*0.120 = 15.96%

however the beer factor is different
0.120/14% = 8.5
So the factor here is 8.5

So something's skewiff with your figures.

if 14% is right, then your OG could be 14%/133 = 105 points change. so 1.105 in total.

I hope this helps somewhat, I'm not sure if I've answered your question or just given you more to think about.

MeaderBaker
02-05-2011, 11:41 AM
My hydrometer has Specific Gravity and Potential Alcohol. When I first measured it, I got the reading of 1.2 SG
That was November 15 2010
Measuring it again today, I got 1.0 SG

Using bakers yeast as per recipe. Tolerance of 12%

The 133 comes from the Beginners guide.

Medsen Fey
02-05-2011, 01:04 PM
This gets easier if you will put your hydrometer readings out to 3 digits. When you say you got 1.12 is that 1.102 or 1.120?

If it was 1.120 that has a potential alcohol of nearly 16% and if it went to 1.000 then yes, you are close to 16% ABV - the 133 number works reasonably well. All these calculations are rough estimates at best.