On 1 kg of wholemeal bread: 2,5 dkg of yeast. 20 dkg of sugar, 2,5 dkg of mint, 5 dkg of raisins, 8—10 liters of water.
Brown the rusks of the rye bread, put into the pot, pour boiling water, cover and leave for 3-4 hours. Put the yeast into the drained liquid, sugar and mint. Cover with a clean napkin and let it ferment for 5-6 hours. When foam appears, strain again and pour acid into bottles. Put a few raisins in each, cork tightly with boiled corks, tie them with twine 1 put in a cool place. After three days, the acid will be safe to drink.