So, today I decided to ferment myself some kvass! For those that don't know, kvass is a Slavic beverage, made with black bread, I used authentic Estonian black bread, any dark bread will work. Raisins, sugar, and yeast! Iv put together a bottle of kvass, with four cups of water, one teaspoon of yeast, and a whole cup of sugar. Now as I understand it, for that much it'll take about two days for it to be ready to drink. But I'm trying to figure out what the alcohol content would be. And what it can be if I ferment it longer. Please if you can help at all, respond!
A cup of sugar, in one quart!? Did you take an original gravity reading? Otherwise some complex calculations will be necessary. First of all it depends on how much bread you used. When I made kvass last year, I figured I got 10 gravity points per pound per gallon from the bread, which equates to 2.5 points per ounce per quart. So for your one quart, multiply how many ounces of bread are in there by 2.5. If you don't know exactly how much bread you used, well then... Sugar will give about 21 points per cup per gallon, so in a quart that's 84 points... whoa... Raisins, again, it will depend on how many you use, but it will just make the kvass even stronger of course. Ignoring the raisins for now... Waiting a couple of days, maybe your specific gravity will drop by a third or something like that. So... Assuming we use say 4 ounces of bread, that's 10 points, plus 84 points from the sugar, that's 1.094 for an original gravity even without any raisins. Then take that down to say 1.065 after a couple of days.... You'll end up with an extremely sweet bready beverage of anywhere from 2-7% ABV, depending on how much bread and raisins you used, and the specific timing of when you drink it... and I hope it's not in a sealed glass container or else it will certainly explode. Next time use a small fraction of the sugar, or none at all, and enjoy a more traditional beverage of about 1% ABV. Good luck.
Wow, that happened really fast. The recipe you used might actually work okay for a full gallon of kvass, but not just one quart. Even so, I would still avoid glass. If you can use plastic bottles, that is best for kvass.
Kvass could be done a bunch of ways. I did a beet kvass by hanging yogurt in the fridge and using the whey drippings to ferment the beets. I think it had 1-2% alcohol.
