S. cerevisiae yeasts are exposed to various stress factors during alcoholic fermentation, such as high temperature and high concentration of substrates and products. Yeast can be effectively protected from all this with microencapsulation, which is gaining an increasing role in biotechnology and food industry. In the master's thesis, yeasts S. cerevisiae were encapsulated in alginate using a device with an electrostatic vibration nozzle, and various cyclodextrins were added to some samples. We monitored the course of alcoholic fermentation and the effect of low (8 %) and high (28 %) glucose concentration in the culture medium and the addition of β-CD, β-CD citrate, and β-CD maleate on the yield of alcoholic fermentation. The release of yeast from the microspheres was monitored by measuring the OD650 and the amount of ethanol produced, and glucose consumed was analysed by the HPLC method. Using the LC-MS/MS method, we analysed the effects of all the mentioned factors on the proteomic level. We found that encapsulation with alginate successfully protects yeasts from high glucose concentrations and enables higher fermentation yields (up to 97%). This was also indicated by increased levels of proteins involved in amino acid biosynthesis and glycolysis/gluconeogenesis. The addition of 0,2 % cyclodextrins affects the increased permeability of the hydrogels, where the encapsulated yeasts achieved comparable growth, a lower yield, and a reduced level of almost 70 % of proteins compared to free yeasts. Furthermore, it is expedient to study the influence of higher and lower concentrations of added cyclodextrins, more biological repetitions during a longer monitored period of fermentation and the influence of the yeast population along the bead diameter.
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