NON-FOAMING MUTANTS OF SAKÉ YEAST COMPARISON OF THE CELL WALL COMPOSITION BETWEEN THE PARENT AND MUTANTS

Abstract

Non-foaming mutants of Saké yeast (Saccharomyces cerevisiae) which do not form froth head during fermentation differ in various physicochemical properties from their parent strain. In the work, the cell wall composition was compared between parent strain and two strains of the mutant. Flotability of the mutant cells increased by mechanical disruption of the cells, suggesting that the disrupted cells have higher flotability regardless of the kind of yeasts, i.e., foaming or non-foaming. Contents of total carbohydrate, nitrogen, ash, glucan, mannan, glucosamine, and phosphorus as well as amino acid composition were determined repeatedly. Results showed that there were no marked differences in the cell wall composition between the parent and mutant strains, as can be detected directly by the ordinary chemical analyses.