material and energy costs.
In this paper, the authors outline separate results of their research in the areas of
improving the technology and equipment for the synthesis of baking yeast.
The ratio of matter flows. Anaerobic and aerobic fermentation processes are parts
of the general carbon cycle with its biotic and abiotic components in a large number of
processes. The chain of transformations of synthesized sugars and other natural polymers
begins with the participation of such substances as water, carbon dioxide, solar energy,
and chlorophyll as a natural catalyst. The cycle means the presence of both destructive
processes, which simplify the substances involved in them, and the processes of synthesis,
which create incomparably more complex organic structures used as building blocks for
flora, fauna and, finally, man. At the same time, the processes of destruction and,
simultaneously, synthesis in aerobic and anaerobic fermentation are synchronized with
different matter and energy costs. The creation of alcohol and carbon dioxide by the yeast
can be estimated at the destruction stage, whereas the synthesis and biomass growth of
microorganisms should clearly be attributed to the creation of biological constructs of the
highest quality in the living world. The intensity and overall result of such synthesis are
determined by the presence of nutrition, thermodynamic conditions and the presence of
dissolved oxygen. Nutrition of microorganisms occurs in the process of constant
metabolism between them and the medium and is accompanied by a combination of
chemical reactions that determine growth, self-renewal, development, and increase of
biomass. In this case, the energy supply relies on the decomposition of complex nutrients
and oxidation of chemical compounds. The experience of technical microbiology
indicates that the growth rate of biomass or the synthesis of target substances is
determined, firstly, by the natural properties of microorganisms and, secondly, by the
conditions of the culture medium. The latter are the impact factors that can be realized.
Based on this, the fermentation processes are divided into aerobic and anaerobic ones
depending on the presence or absence of dissolved oxygen in the medium. An example of
the effect ranges and possibilities is the technology of synthesizing baking yeast, the
effectiveness of which in other equal conditions is determined by the presence of dissolved
oxygen. According to the data [1, 2], O
2
in the amount of 25% to liquid phase saturation
no longer restrains the aerobic synthesis and the formation of alcohol ceases with the
maximum yield of microbial culture. However, there is a contradiction within the
parameters of influence, associated with selecting the temperature of the medium. The
temperatures of 28–32 °С are optimal for Saccharomyces yeast, but the solubility of
oxygen, as well as other gases, decreases when the temperature increases. Additionally,
oxygen refers to gases with limited solubility, which leads to using special measures in
the equipment and technologies of culture media aeration. The requirements for dynamic
delivery of oxygen to the medium are estimated according to the expected rate of biomass
growth of yeast based on the processes of complete oxidation of glucose, which is
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