Kvasny Prum. 1977; 23(12): 274-281 | DOI: 10.18832/kp1977044

Dynamic of contamination by Asporogenous yeast of Saccharamyces cerevisiae in the cultivation stage.Peer-reviewed article

L. N. MENDELSON, L. S. MALINOVSKIJ

Simultaneous propagation of Saccharomyces cerevisiae and asporogenous yeast in the inflow type propagators , can be  described with a system of differential equations. If beside Saccharomyces only one kind of foreign yeast is present, the conditions can be expressed by two differential equations. Their solution shows the relative proportion of foreign yeast in the system and its changes. The article deals with the dynamic propagation of  contaminating microorganisms and with the equation for two methods of continuous cultivation, viz. in turbidistats and chemostats. Hogh contamination of Saccharomyces cerevisiae in final  stages of aerobic cultivation in inflow plants is due mainly to the contamination of pure primary culture used as starter. In the final commercial stage of yeast production, the principal parameter determining the quality of yeast and duration of the process, is the concentration of foreign yeast in the seed yeast. Asporogenous yeast, which may get into the vessel with the nutrient medium or with air, has practically no effects upon the dynamic characteristic of the process.
(In Slovak, English summary only)

Keywords: Saccharomyces cerevisiae, contamination, cultivation

Published: December 1, 1977