h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Roughly how alcoholic is it?

You have to have some gravy with everything!

Use a hygrometer to measure the difference between original gravity and the specific gravity. then compare this with a brewers table to give you a calculation of ABV.
As a rule of thumb the more sugar and food and longer the fermentation the stronger the brew, too strong though and it will kill the yeast and too sweet undrinkable!

Can I suggest that a better instrument for checking specific gravity (alcohol content) would be a hydrometer.

I agree. Read you hydrometer after you have added any sugar and again when you are ready to drink it. The first reading will give you the potential alcohol (abv) reading and the second (usually at 1.000) will show you if all the necessary sugar has been converted to alcohol. Subtract one from the other (using the aforementioned hydrometer table) and you will have an indication of the alcohol content.

May I suggest using champagne yeast. This will give you a fermentation under pressure (a wide variety of dried yeasts would be available from a home brew shop.

Thanks for your comments. It's great to have such expert knowledge backing up our Entries here.