question on measuring alcohol potential

kazmerzakr · Jan 7, 2011

Please help me with this hypothetical question that isn't all that hypothetical if you catch my drift....

Assume the starting SG of a must is 1.2, with a potential alcohol level of about 15.5% (yes, I know, too high, but bear with me on this)
Assume fermentation takes the SG down to 1.07 before it becomes stuck. At 1.07 the alcohol potential is now about 9%
Can one subtract 9% from 15.5% and come to the conclusion that the must now has 6.5% alcohol ? Does it work that way?

AlFulchino · Jan 7, 2011

just use this simple formula...starting sg minus ending sg divided by .0074 and that gives you what you need....

cpfan · Jan 7, 2011

kazmerzakr said:
Please help me with this hypothetical question that isn't all that hypothetical if you catch my drift....

Assume the starting SG of a must is 1.2, with a potential alcohol level of about 15.5% (yes, I know, too high, but bear with me on this)
Assume fermentation takes the SG down to 1.07 before it becomes stuck. At 1.07 the alcohol potential is now about 9%
Can one subtract 9% from 15.5% and come to the conclusion that the must now has 6.5% alcohol ? Does it work that way?

Before you start doing any arithmetic on your readings, you need to get your readings correct. First they should always be quoted as 3 decimal places.

Second, does 1.2 mean 1.200, 1.020, or 1.002. Cause none of them work out to 15.5%. However, 1.120 does.

So, 1.120 - 1.070 = .050 * 133 = 6.65%

Steve

kazmerzakr · Jan 7, 2011

Thanks, Steve for setting me straight. I should have been more careful with my numbers, and 1.120 is the number to work with. I follow your answer and appreciate the response.