Dissolve 140 gr of baker's yeast in 500 mL of a 0.10 M aqueous solution of sodium bicarbonate for about 15 hours at 35 degree C in a tightly sealed reagent bottle.

  100 ml ethanol is added to 500 mL of fresh yeast extract, for a final ethanol concentration of 29% (by volume).
   300 ml of solution is needed for 50 kg sugar.

Example: 14 gr yeast in 50 mL of 0.10M (0.42 gr soda) aqueous solution of sodium bicarbonate for about 15 hours at 35 degree C. 10 ml ethanol is added. 30 ml of solution per 5 kg sugar.

Example: 7 gr yeast in 25 mL of 0.10M (0.21 gr soda) aqueous solution of sodium bicarbonate for about 15 hours at 35 degree C.  5 ml ethanol is added. 15 ml of solution per 2.5 kg sugar.

Example: 2.8 gr yeast in 10 mL of 0.10M (0.1 gr soda) aqueous solution of sodium bicarbonate for about 15 hours at 35 degree C.  5 ml ethanol is added. 7 ml of solution per 1 kg sugar.


  In 100 ml (2:1) syrup are 90 gr sugar. In 20 drops syrup in 100 ml water are 900 mg sugar. 450 mg glucose are equal to 100% inversion. 8 gr yeast per 1 kg sugar.
  In 100 ml (1:1) syrup are 60 gr sugar. In 20 drops syrup in 100 ml water are 600 mg sugar. 300 mg glucose are equal to 100% inversion. 6 gr yeast per 1 kg sugar.

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