Peter's Kvass - Cold beverage.

Recipe. Russians drink Mint kvass is a cold beverage. 

Ingredients to make Kvass:

800 g (2 lb) old black bread
4 litres (8 pint) water
20 g (1 oz) fresh yeast
100 g (4 oz) sugar
1/4 cup lukewarm water (110 - 115 F)
50 g (2 oz) crumbled dried mint leaves
50 g (2 oz) raisins
100 g (4 oz) finely grated horseradish
100 g (4 oz) honey

Method:

1. Preheat the oven to 200 F. Place the chopped coarsely bread in the oven for about 1 hour, or until it is thoroughly dry and brown. 

2. Bring 6 quarts of water to a boil in an 8-quart casserole and drop in bread. 

3. Remove from heat, cover loosely with a kitchen towel, and set it
aside for 3 -4 hours. 

4. Strain contents of the casserole through a fine sieve set over another large pot or bowl, pressing down hard on the soaked bread with the back of a large spoon before discarding it. 

5. Sprinkle the yeast and 1/4 teaspoon of the sugar over the 1/4 cup of lukewarm water and stir to dissolve the yeast completely. Set aside in a warm, draft-free spot (such as an unlighted oven) for about 10 minutes, or until the mixture almost doubles in volume. 

6. Stir the yeast mixture, the remaining sugar and the mint into the strained bread water, cover with a towel, and set aside for 5 -6 hours. 

7. Strain the mixture again through a fine sieve set over a large bowl or casserole, add honey and finely grated horseradish. Stir thoroughly, then prepare to bottle kvass. You will need 2 - 3 quart-sized bottles, or a gallon jug. Pour the liquid through a funnel 2/3 of the way up the sides of the bottle. Then divide the raisins among the bottles and cover the top of each bottle with plastic wrap, secured with a rubber band. 

8. Place in a cool -- but not cold -- spot for 2 - 3 days, or until the raisins
have risen to the top and sediment has sunk to the bottom.
Carefully pour off the clear amber liquid and re-bottle it in the washed bottles. Refrigerate until ready to use. Although Russians drink kvass as a cold beverage, it may also be used as a cold-soup stock in okroshka (chilled vegetable soup with meat) or botvinia (green vegetable soup with fish).