📝 About This Recipe
Known as 'Liquid Bread,' Kvass is a legendary Slavic fermented beverage with a history stretching back over a thousand years. This sparkling, probiotic-rich drink offers a complex profile of toasted rye, tangy sourdough notes, and a subtle sweetness balanced by a refreshing effervescence. It is the ultimate thirst-quencher, capturing the rustic soul of Eastern European summers in every probiotic-packed sip.
🥗 Ingredients
The Bread Base
- 500 grams Dark Rye Bread (Ideally sourdough rye or Borodinsky bread, cut into 1-inch cubes)
- 4 liters Filtered Water (Chlorine-free is essential for fermentation)
Sweeteners and Fermentation Starters
- 150 grams Granulated Sugar (Adjust based on desired sweetness)
- 1/2 teaspoon Active Dry Yeast (Or 2 tablespoons of active sourdough starter for a more traditional tang)
- 1/4 cup Warm Water (For blooming the yeast)
Flavor Enhancers and Carbonation
- 15-20 pieces Raisins (Organic and unsulphured preferred; helps with carbonation)
- 1 small sprig Fresh Mint (Optional, for a bright finish)
- 1 tablespoon Honey (Optional, for a deeper floral sweetness)
- 1 teaspoon Lemon Juice (To balance the pH and add brightness)
👨🍳 Instructions
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1
Preheat your oven to 350°F (175°C). Spread the rye bread cubes on a baking sheet and toast them for 20-30 minutes, or until they are very dark brown and completely dried out. The darker the toast (without burning), the deeper the color and flavor of your Kvass.
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2
In a large stockpot, bring 4 liters of filtered water to a rolling boil. Once boiling, remove from heat and carefully add the toasted bread cubes.
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3
Cover the pot with a clean cloth or lid and let the bread steep for 4 to 6 hours. The water will turn a deep amber color, resembling dark tea.
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4
After steeping, strain the liquid through a fine-mesh sieve lined with cheesecloth into a clean 5-liter fermentation jar or glass carboy. Squeeze the bread gently to extract all the flavorful liquid, but don't mash it too much or the drink will be cloudy.
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5
In a small bowl, dissolve the sugar (and honey, if using) in 1 cup of the warm bread liquid, then stir this mixture back into the main jar.
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6
In a separate small cup, bloom the yeast in 1/4 cup of warm water (about 100°F/38°C) for 10 minutes until it becomes frothy.
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7
Ensure the main bread liquid has cooled to room temperature (below 90°F/32°C). Stir in the activated yeast and the lemon juice.
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8
Cover the jar with several layers of cheesecloth secured with a rubber band. This allows gases to escape while keeping fruit flies out.
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9
Place the jar in a warm, dark spot (70-75°F) and let it ferment for 12 to 24 hours. You should see small bubbles rising to the surface and a slight foam appearing.
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10
Taste the Kvass. It should be slightly tangy and bubbly. If it's to your liking, prepare your glass flip-top bottles by placing 2-3 raisins in each bottle.
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11
Carefully siphon or pour the Kvass into the bottles, leaving about 2 inches of headspace at the top. Seal the bottles tightly.
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12
Let the bottled Kvass sit at room temperature for another 4-8 hours to build carbonation. Check one bottle by opening it slightly; if it hisses loudly, it’s ready.
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13
Transfer the bottles to the refrigerator immediately. Chill for at least 24 hours before serving. This halts the fermentation and allows the flavors to mellow.
💡 Chef's Tips
Always use filtered water, as chlorine can kill the beneficial yeast and bacteria needed for fermentation. The secret to a rich, dark Kvass is almost burning the bread; aim for a deep chocolate brown color during the toasting phase. If your Kvass is too sour, shorten the initial fermentation time; if too sweet, let it sit out longer before refrigerating. Be cautious when opening bottles! Natural carbonation can be powerful, so always open them over a sink after they have been thoroughly chilled. For a more authentic 'forest' flavor, add a few dried birch leaves or a handful of wild berries during the bottling stage.
🍽️ Serving Suggestions
Serve ice-cold in a tall glass, garnished with a fresh mint leaf for a refreshing summer cooler. Use it as the base for 'Okroshka,' a traditional Russian cold soup made with cucumbers, radishes, and boiled potatoes. Pair with hearty, salty snacks like smoked fish, pickles, or dark rye bread with salted butter. Enjoy as a probiotic alternative to soda or beer during a heavy meal to aid digestion. Mix with a splash of vodka and a squeeze of lime for a unique, Slavic-inspired cocktail.