Homemade Bread Kvass with a Hint of Caramel and Mint

Preheat the oven to 180°C (fan) or 200°C (top-bottom). Cut the whole grain bread into cubes with sides of about 2-3 cm. Don't worry if the cubes are not perfectly even. Spread them evenly on a large baking sheet lined with parchment paper.

Place the baking tray with the bread in the preheated oven. Bake for 20-25 minutes until the bread becomes very dry, hard, and deeply browned, almost on the verge of burning (but not burnt!). The pieces should have a dark brown color. Halfway through baking, stir them with a spatula to ensure they toast evenly. This step is crucial for achieving a deep color and flavor of the sourdough.

Prepare a large pot or jar with a capacity of at least 5 liters. Pour the hot, baked bread crumbs into it. Boil 4 liters of water in a kettle. Carefully pour the boiling water over the bread. Gently stir with a wooden spoon to ensure all pieces of bread are submerged. Cover the container with a clean cloth and set it aside at room temperature for 6-8 hours, or preferably overnight.

Prepare a second large container. Place a large sieve lined with double-layered cheesecloth or a clean dish towel on top. Slowly pour the contents of the first container through the sieve to separate the liquid (wort) from the soaked bread. Once most of the liquid has drained, gather the corners of the cheesecloth and squeeze out the remaining liquid from the bread. Every drop is precious!

In a small, dry skillet or a saucepan with a thick bottom, place 100g of brown sugar. Heat over medium heat, without stirring, until the sugar melts and turns into a liquid, dark caramel. When the caramel starts to smoke, carefully pour in about 100 ml of the previously prepared wort (bread liquid). Be careful, it will splatter a lot! Stir vigorously until the caramel completely dissolves in the liquid. Pour the caramel solution into the rest of the wort and add the remaining 50g of sugar. Stir until dissolved.

Cool the wort to a temperature of about 30-35°C. This is very important – too hot liquid will kill the yeast. In a small bowl, place the crumbled fresh yeast, add a teaspoon of sugar (from the 50g) and pour in 50 ml of lukewarm wort. Mix until the yeast dissolves and set aside for 10-15 minutes. The active yeast should start to foam. Pour the activated yeast starter into the main vessel with the wort and gently mix.

Cover the container with a clean cheesecloth or towel and secure it with a rubber band or string. The fabric will allow gases to escape while protecting the drink from insects and contaminants. Place the container in a warm, non-sunny spot (e.g., near a radiator or in a turned-off oven with the light on) for 24-48 hours. After about 12 hours, a foam should appear on the surface, and the drink will begin to emit a characteristic sour smell.

After the first fermentation is complete (when the taste is balanced), remove the foam from the surface. Wash the raisins and mint sprigs thoroughly. If using, grate the lemon zest. Pour the liquid through a strainer into clean, sterilized thick glass bottles with swing-top closures (like Grolsch). Add a few raisins and a sprig of mint (and a pinch of lemon zest) to each bottle. Leave 3-4 cm of headspace at the top.

Seal the bottles tightly and leave them at room temperature for another 12-24 hours. During this time, the remaining sugar and yeast will produce carbon dioxide, which will naturally carbonate the drink. The longer they sit, the fizzier they will become.

When the kvass reaches the desired level of carbonation, transfer all the bottles to the refrigerator. Low temperature will stop the fermentation process and allow the drink to clarify. Kvass tastes best when served very chilled. Serve in tall glasses. Enjoy!