The development of a non-foaming mutant of Saccharomyces cerevisiae

The non-foaming mutant of the brewery production top-fermenting ale strain Saccharomyces cerevisiae was induced by serial repitching of bottom-cropped yeast. The concentration of total protein and hydrophobic polypeptide in wort fermented with the non-foaming mutant and its parent strain was determined in order to elucidate their effect on the formation of a yeast head during beer fermentation. A slight difference in the quantity of total protein in beer fermented with the non-foaming mutant and its parent strain was found. In turn, there were not any systematic differences in hydrophobic polypeptides. Simultaneously, organoleptic properties of green beer fermented with the non-foaming mutant and the original strain were checked and significant variations were observed. Large variations were also found in attenuation of these beers and in the viability of the bottom-cropped non-foaming mutant and the top-cropped parent strain collected after successive fermentations. © 2000 Elsevier B.V. All rights reserved.