The use of dry microorganisms in the production of kvass

One of the ways to improve kvass production is the use of dry microorganisms in the technology. The work shows the possibility of using such dry microorganisms as "Saf-instant", "Saf-levur", "Fermipan brown", "Nevada" at the fermentation stage. Yeasts were used for fermentation of kvass wort obtained by infusion method on the basis of barley, unfermented rye and fermented rye malts. Yeast cultures were pre-watered for 1 hour before use, then introduced into the wort in the amount of 20 million cells/cm3. During the experiment the fermentation process was monitored by the reduction of dry matter in the fermented kvass, as well as the physiological state of yeast during the whole fermentation period. The duration of fermentation to the required dry matter content in fermented kvass (5.6-5.8%) was 15 hours for "Nevada" microorganisms, 18 hours for "Saf-instant" and "Saf-levur", 20 hours for "Fermipan brown". It was noted that all yeasts adapted to fermentation conditions rather quickly, on average in 3-5 hours, their active reproduction was observed. Yeast biomass increased on average by 3.5 times, high content of viable cells and cells with glycogen (up to 74-81%) was observed. The fastest growth of yeast biomass, including cells with glycogen, was observed in the case of baker's yeast "Nevada", a longer accumulation of yeast during fermentation was observed for the sample of yeast "Fermipan brown". The obtained variants of kvass had good organoleptic characteristics, quality indicators corresponded to the required standards. The proposed technology can be recommended for implementation in existing beer and soft drinks enterprises.