Glycerol → L-Ascorbic Acid

Participants

Reaction Steps

The fourth and final fermentation step is performed in a 15000-liter vessel with the inoculation from step no 3. The fermentation is performed at 37° C. for 9 to 12 hours with stirring and pH control. At the start of the fermentation the pH is 6.5. The pH control starts when the pH drops below 5.4 using a 20% sodium hydroxide solution. The pH control is set to pH 5.5. 100 mM glycerol is added in the final phase of the fermentation, just before the culture reaches the stationary phase. The fermentation is complete when the culture reaches the stationary phase, which can be seen by the reduction of the addition of the sodium hydroxide solution. Roughly 930 liters of the sodium hydroxide solution is added to the 10200 liters of media and 600 liters of inoculum during the fermentation.

Provenance & Evidence