ALC/VOL measurement
Moderator: Site Moderator
ALC/VOL measurement
I have recently noticed that my measurements of alc/vol are off after the addition of sugars. I am theorizing that this must be due to the relative density of the sugar which makes the alcohol measure lower than it really is.
You are 100% correct.
Remember that pure water has a S.G. of 1.00 When you add sugar, that goes up. So when you start your ferment, the SG might be something like 1.10, and then when the yeast eats away the sugar and replaces it with EtOH, that SG will drop.
The best way to compute %ABV (percent alcohol by volume), is to use an alcoholometer on a solution at the proper temperature. This should ONLY be done on the exact stuff that came off the end of the still. Then, you will KNOW (or can compute) exactly how much EtOH you have. Then when you add sugar (or other things), you know the volume of EtOH (100% pure) which you started with, then you can measure the final volume of your finished booze, and then you can compute the ABV of the final product.
You can not easily test ABV strength of finished product when you have added sugar or other adjuncts to your stuff. The readings simply will not be right, unless you are using a hydrometer which is "tuned" to the exact stuff you have added. A hydrometer like this, would probably be built specifically for a commercial producer, who add the same amount of sugar/glycerin/whatever to his product, and does so for each batch. However, if you simply measure prior to mixing, then you "can" determine the strength even after you have doctored up the product to whatever flavor you want.
H.
Remember that pure water has a S.G. of 1.00 When you add sugar, that goes up. So when you start your ferment, the SG might be something like 1.10, and then when the yeast eats away the sugar and replaces it with EtOH, that SG will drop.
The best way to compute %ABV (percent alcohol by volume), is to use an alcoholometer on a solution at the proper temperature. This should ONLY be done on the exact stuff that came off the end of the still. Then, you will KNOW (or can compute) exactly how much EtOH you have. Then when you add sugar (or other things), you know the volume of EtOH (100% pure) which you started with, then you can measure the final volume of your finished booze, and then you can compute the ABV of the final product.
You can not easily test ABV strength of finished product when you have added sugar or other adjuncts to your stuff. The readings simply will not be right, unless you are using a hydrometer which is "tuned" to the exact stuff you have added. A hydrometer like this, would probably be built specifically for a commercial producer, who add the same amount of sugar/glycerin/whatever to his product, and does so for each batch. However, if you simply measure prior to mixing, then you "can" determine the strength even after you have doctored up the product to whatever flavor you want.
H.