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Fermentation · From Bladwijzer

Birch kvass

Updated on 9 October 2026

• Makes: 2 litres
• Time: 15 min + 3–5 days
• From: Downy birch

Ingredients

• 2 litres fresh birch sap
• 2 tablespoons sugar
• 1 handful unwashed organic raisins (± 20)
• 1 strip of unwaxed lemon peel

Method

1. Dissolve the sugar in the sap.
2. Pour it into strong swing-top bottles and divide the raisins and lemon peel between them. Leave 5 cm of headspace.
3. Leave at room temperature for 2 to 4 days, until lightly fizzy. Release the pressure once a day.
4. Then move the bottles to the fridge.

Storing: Drink chilled within a week. Open carefully over the sink; the drink contains a trace of alcohol.