Improved properties of baker's yeast mutants resistant to 2-deoxy-D-glucose

We isolated spontaneous mutants from Saccharomyces cerevisiae (baker's yeas t Vl) that were resistant to 2-deoxy-D-glucose and had improved fermentativ e capacity on sweet doughs. Three mutants could grow at the same rate as th e wild type in minimal SD medium (0.17% Difco yeast nitrogen base without a mino acids and ammonium sulfate, 0.5% ammonium sulfate, 2% glucose) and had stable elevated levels of maltase and/or invertase under repression condit ions but lower levels in maltose-supplemented media. Two of the mutants als o had high levels of phosphatase active on 2-deoxy-D-glucose-6-phosphate. D ough fermentation (CO2 liberation) by two of the mutants was faster and/or produced higher final volumes than that by the wild type, both under labora tory and industrial conditions, when the doughs were supplemented with gluc ose or sucrose. However, the three mutants were slower when fermenting plai n doughs. Fermented sweet bakery products obtained with these mutants were of better quality than those produced by the wild type, with regard to thei r texture and their organoleptic properties.