Product and redox potential analysis of sauerkraut fermentation.

The relationships between the redox potential of the brine, during fermentation of white cabbage into sauerkraut of two early and two late fermentation processes, and the changes in the amount of sugars, organic acids, the redox potential of the brine and of the ascorbic acid redox couple, and pH are described. The trend in the change of the redox potential of the brine is the same for all four fermentation processes studied. In the first phase a sharp decrease in redox potential is followed by an increase in redox potential. In the second phase the redox potential is rather constant. This second phase is followed by another decrease in redox potential, which stabilizes at a minimum value, the third phase. It was observed that sugar fermentation and acid production mainly took place during the first and third phases, probably representing, respectively, the heterogeneous and homogeneous fermentation processes.