CHARACTERIZATION OF THE YEAST POPULATION FROM TRADITIONAL CORN AND RYE BREAD DOUGHS

Yeasts were isolated from a variety of home-made bread doughs and iden tified. A pure culture of Saccharomyces cerevisiae was found in 18% of the doughs, The same species predominated in 80% of the doughs examin ed whereas Issatchenkia orientalis, Pichia membranaefaciens and Torula spora delbrueckii were present in about 40% of the samples, About one quarter of the isolates displayed killer activity, strains of P. anoma la showing the broadest spectra. Two isolates of S. cerevisiae and thr ee of T. delbrueckii gave biomass values in sucrose medium similar to or higher than those obtained with commercial compressed baker's yeast strains.