Russian kvass is a lightly sparkling fermented drink made from toasted rye bread, water, sugar, and a small amount of yeast.
Toasting the bread gives the drink its deep color and malty flavor. A short fermentation creates gentle fizz without making kvass taste strongly alcoholic.

Taste the kvass during fermentation. Bottle it as soon as it is pleasantly tangy, then chill it promptly to slow the fermentation.
Serving Suggestions
Serve kvass very cold in glasses with ice, mint, or a slice of lemon. It is also traditionally used in cold summer soups.

Recipe Notes
Keep bottled kvass refrigerated and enjoy within 5 days. Open carefully because natural carbonation can build quickly.

Russian Kvass
A lightly sparkling rye-bread drink with a malty flavor, gentle tang, and refreshing natural carbonation.
Equipment
- Large saucepan
- Large glass jar
- Fine-mesh strainer
- Funnel
- Swing-top bottles
Ingredients
Kvass base
- 1 lb dark rye bread cut into cubes
- 8 cups water plus more for topping up
- 1/2 cup granulated sugar
- 1/4 tsp active dry yeast
- 2 tbsp raisins
Serving
- 2 sprigs fresh mint for serving
- 1 lemon cut into wedges, optional
Instructions
Toast and steep the bread:
- Heat the oven to 350°F (175°C). Spread the rye bread on a baking sheet and toast for 15 to 20 minutes, until deeply browned but not burned.
- Bring the water to a boil in a saucepan. Remove from the heat, add the toasted bread, cover, and steep for 4 hours.
Ferment:
- Strain the bread infusion into a clean glass jar. Stir in the sugar and yeast, then cover loosely with a clean cloth.
- Leave at room temperature for 12 to 24 hours, tasting after 12 hours until the drink is lightly tangy and gently fizzy.
Bottle and chill:
- Strain the kvass again and pour it into clean swing-top bottles, adding a few raisins to each bottle. Leave a little headspace.
- Let the bottles stand at room temperature for 2 to 4 hours, then refrigerate until cold. Serve with mint and lemon if desired.
Notes
- The fermentation time varies with room temperature; warmer kitchens work faster.
- Kvass contains very little alcohol when fermented briefly, but it is not completely alcohol-free.
Nutrition
Calories: 80kcalCarbohydrates: 19gProtein: 1gSodium: 90mgFiber: 1gSugar: 14g