Measuring Abv Of Eis Brew

[barto1308]

As the topic says, how can we do this as homebrewers? Has anyone done it with any success? I have accidentally made an Eisbock when lagering a bock I made a while ago - I let it thaw out to a regular bock - but I certainly could have removed a fair amount of ice if I wanted to.
Would it work to measure the amount of ice removed (assuming it is all water), compare original volume to final volume, and back calculate the ABV based on last gravity reading, similar to how wort SG is calculated pre and post boil?

 

[zebba]

To do it you need to take a refractometer reading and a hydrometer reading of the final beer. You don't need an OG. I then put it into beersmiths refractometer tool, although there are plenty on the web if you don't have beersmith. If you have a refrac you probably have access to such a tool. If you don't have a refrac, me linking to a tool probably won't help

You can also use this technique to calculate original gravity of comercial beers, and things like that. It's pretty useful if doing clones, for example.