Continuous glycerol production by the sulphite process with immobilized cells of Saccharomyces cerevisiae

Glycerol fermentations by the sulphite process with immobilized yeast cells were carried out successfully in continuous culture in a fixed-bed column reactor. In comparison to continuous glycerol fermentations with free yeast cells, fourfold higher dilution rates were obtained. The stability of the immobilized cell system was dependent on dilution rate (D) and temperature. Glycerol yields were influenced by the ratio of sugar to Na2SO3 in the feed. At a flow rate of D = 0.06 h −1 glycerol concentrations up to 25 g1 −1 were measured in the effluent with an average volumetric productivity of 35 g 1 −1 per day. A constant production rate was maintained for nearly 9 months.