The aim of this study was to quantify the amount of specific components in the cell wall of yeast Saccharomyces cerevisiae, namely mannoproteins, β-1,3-glucans and β-1,6-glucans and chitin using newly developed enzymatic and chemical method. These new methods were validated on various cell wall mutants and it was observed that growth conditions have strong effects on the amount of cell wall components. This method was used to evaluate cell wall composition of industrial yeasts (autolysed and dried yeast) that were subjected to different fermentation and treatment processes. The phenotypic assay was used to confirm and to notice how the growth of various strains depends on composition of medium. The second part of the project was to examine the effect of ethanol stress on cell wall composition and to analyze cell wall composition in industrial yeast cells, to determine whether culture/process conditions have an impact on cell wall composition.