Robintun

08-10-2010, 09:29 PM

Hello all, been a long time since I posted and have 27 batches under my belt but math still confuses me. I searched and found a number of posts as well as the Mead Calculator to figure this out and was hoping someone would help me see if I am calculating my Alcohol content by volume correctly. The issue is I was adding honey as time went on. I am hoping my calculations are right as I am currently making a braggot that I was hoping to add additional honey and water to over the next few weeks as I was able to extract more from out hives.

The calculation I am wondering about to see if I understand this right is:

1) So I started with a blueberry mead with 12 pounds of honey in a total of 6 gallons with a O.G. of 1.088. Yeast was Lalvin 71B-1122 though as far as I can tell that should not matter for the calculation (?). Temperatures of SGs only varied by about 2-3 degrees over time so I am not considering that as a significant change either.

2) later the SG 1.011 and added 1 pound 13.5 ounces more of honey stirred and new S.G. at 1.023

3) later the SG 1.004 and added 1 pounds 6 ounces of honey and stirred with new S.G. at 1.010

4) FG was 1.003

So as best I can tell the calculation would go:

ABV = (OG-FG)*131.25

13.5=(1.088-[1.003 -{1.023-1.011}-{1.010-1.004}]*131.25

13.5=(1.088-0.985)*131.25

If I use the PAC on my hygrometer: it goes from 12% down to about 1.5% and then up to close to 3.5% then to 0.5% then to 1.5% and finally 0.5%. Therefore around 14.5%.

Averaging the two ways of doing it I am assuming it is around 14% ABV, but I would really appreciate input from someone who is familiar with these calculations.

The calculation I am wondering about to see if I understand this right is:

1) So I started with a blueberry mead with 12 pounds of honey in a total of 6 gallons with a O.G. of 1.088. Yeast was Lalvin 71B-1122 though as far as I can tell that should not matter for the calculation (?). Temperatures of SGs only varied by about 2-3 degrees over time so I am not considering that as a significant change either.

2) later the SG 1.011 and added 1 pound 13.5 ounces more of honey stirred and new S.G. at 1.023

3) later the SG 1.004 and added 1 pounds 6 ounces of honey and stirred with new S.G. at 1.010

4) FG was 1.003

So as best I can tell the calculation would go:

ABV = (OG-FG)*131.25

13.5=(1.088-[1.003 -{1.023-1.011}-{1.010-1.004}]*131.25

13.5=(1.088-0.985)*131.25

If I use the PAC on my hygrometer: it goes from 12% down to about 1.5% and then up to close to 3.5% then to 0.5% then to 1.5% and finally 0.5%. Therefore around 14.5%.

Averaging the two ways of doing it I am assuming it is around 14% ABV, but I would really appreciate input from someone who is familiar with these calculations.