Making an NA beer, how to confirm ABV?

[matt23]

With making an NA beer, after you've heated it for a certain amount of time and temp to get the alcohol out, how do you know for sure if all the alcohol is gone?

I'm making some for people that like good beer but don't want to drink and drive. While I think I may have cooked it long enough, is there any way to know for sure if it's completely gone?

Thanks...

 

[RPh_Guy]

If you got rid of most of it -- which it sounds like you probably did -- unless they're literally drinking it WHILE driving, it really should be ok. Exercise good judgment; don't chug a 6-pack and hop behind the wheel.

If you have a high resolution hydrometer (like this) and a graduated cylinder:
1. Degas and measure a sample of beer 100-250mL.
2. Take a S.G. reading (at the calibration temp of your hydrometer).
3. Boil off half the volume.
4. Chill and then top up back to the exact starting volume with distilled water.
5. Take a second S.G. reading (at the calibration temp of your hydrometer).

The S.G. should be the same if there's no alcohol (less than 0.5% ABV).
A high resolution scale could also be used instead of the hydrometer.

In another thread I suggested a theoretical process for making NA beer without fermenting it. I don't keg so I can't try it, but maybe you could?