You want something cheap and good to receive guests on hot days? - You know, that first of all you have to quench your thirst. So we propose delicious kvass.
Kvass can be prepared with practice, for 2-4 hours before serving.
First you have to cut and dry two handfuls of old rye bread, then brown in the oven. Even if it burns slightly here and there, no worries. Then pour these biscuits with 6-7 liters of hot boiled water. After 10-15 minutes, when the water clears, gently pour it over the bread. Pour 2-3 liters of water a second time, as before and after standing, add to the previous one. Do not squeeze the water from the rusks, because the acid will be cloudy. A lot of water soaks into the bread, so that of this quantity there will be no more than about 5 to 6 liters of kvass.
Now we take 3 or 5 dkg of yeast, rub them with a few teaspoons of sugar, and then together with 2 glasses of sugar and who has, a little citric acid - combine with lukewarm water, Pour the mixed solution into bottles, preferably with hermetic closure (e.g.. after orangeade). When the liquid in the bottles is fermenting, put it in the refrigerator, or to another coolest place in the house. After 3 to 4 hours, the acid is ready.
An additional note here. If we add 3 dkg of yeast, The kvass will be ready after 3-4 hours and it can be kept cool until the next day. But if we do 5 dkg of yeast, the acid will be ready after 2 hours and is unlikely to be stored for the next day.
If we stopper bottles with stoppers, that's attention, because acid can "shoot out."”. Then the corks have to be tied with string to the neck of the bottle.