For 1 litre of kvas:
30-40 g sugar
50 rye rusks
2 g yeast
some raisins

Way of cooking
To get real kvas and make okroshka, you need rye bread or rye rusks, yeast and sugar. To 1 liter of water take 40 - 50 grams of rusks, 30 - 40 grams of sugar
and 2 grams of yeast. Crush the rye rusks or rye bread dried in the oven, put the crumbs in an enameled pan, pour on boiled hot water,mix, cover and leave
for 1-2 hours in a warm place, stirring from time to time. Pour off the liquid, add the sugar and yeast, dissolved in a small amount of cold boiled water, mix and leave for 10 - 12 hours.
When the kvas begins to foam violently, strain it through cheesecloth, pour into sturdy bottles containing 3-4 raisins, cork tightly, and after 2-3 hours
at room temperature, put them in the fridge. After 2-3 days the kvas will be ready to drink.
You can not substitute rye bread (rusks) with something else so you should find it. You can drink kvas as a cold beverage, you can add a leaf of pepper
mint, it will make taste more freshy.

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