Transformation of Sorbitol to Sorbose
L-sorbose is a chemical precursor of L-ascorbic acid (vitamin C), which is used in vitamin preparations and also used as antioxidant in food manufacture. L-sorbose is dehydrogenation of D-sorbitol suboxydans.
Sorbitol is added at an initial concentration of 20% in the nutrient medium consisting of 0.5% yeast extract or maize steep liquor and CaCO3. Fermentation is carried out at 30-35°C with vigorous aeration and agitation. Yields of 90-95% can be obtained in one or two days. L-sorbose is recovered by filtering the medium and by concentrating the filtrate under vacuum to syrup, which crystallizes on cooling. The crystals are washed with ice water and dried.



