In a fermentation process, a cell of a pre-whole genome duplication yeast, which is genetically modified to delete or disrupt a native metabolic pathway from dihydroxyacetone phosphate to glycerol, is cultivated under fermentation conditions and in the presence of a carbon source to produce a desired fermentation product, wherein the glycerol yield is less than 2% based on the weight of the carbon source that is consumed by the cell, and whereby glycerol is added to the fermentation medium.