RU1231872C - Diploid hybrid yeast strain saccharomyces cerevisiae n 5 used for producing liquid yeast - Google Patents

Description

 The invention relates to the food industry and microbiological synthesis and is a new strain used in the production of liquid yeast for the baking industry.

 The aim of the invention is the creation of a strain of yeast with high generative and enzymatic activity, low osmosis sensitivity compared to known strains.

 Strain N 5 has the following morphological and physiological characteristics.

 The size of the cells in a one-day culture on a malt wort with a density of 8% at CB 10.5 9.5 x 8.0 6.0 microns (average 9.0 x 7.0 microns); the shape of the cells is ovoid, round. It sporulates well on an acetate medium, spores 2-3 in aske, the shape of the spores is round, the shell is smooth, dimensions 2.0x 2.0 microns. Colonies on wort agar after 3 days are round, light beige, the middle is conical, convex, the diameter of the colony is 7.0-6.4 mm.

On wort-gelatin form a giant colony with a diameter of 10-15 mm of light beige color, the edges are even, the colony is convex; yeast ferment glucose, fructose, sucrose, maltose, galactose, rhamnose, raffinose, xylose; do not ferment lactose, inositol, sorbitol, dulcite, arabinose, mannitol. Do not digest glycerin, alcohol (ethanol). Ammonium sulfate and ammonium nitrate, urea are assimilated from nitrogen sources, and gelatin is diluted. Citric acid in a concentration of 0.1-0.2% has a stimulating effect on the reproduction energy of the strain. For their development, they require the presence of monosubstituted potassium phosphate and a mixture of trace elements in the medium. Facultative aerobe with optimum growth temperature of 30-32 ° ^C.

Hybrid strain of yeast No. 5 was obtained by vegetatively crossing the haploid cells of a yeast culture belonging to the species Saccharomyces cerevisiae, used to ferment apple juice and subjected to a two-stage irradiation with an incandescent lamp with a power of 100 W for 5 min, followed by growing on a malt wort with a density of 8% at 8% for 10% the addition of 0.1-0.2% citric acid and mineral components (K ⁺ and NH ₄ ⁺ ), which stimulate the activity of a complex of oxidizing enzymes, and haploid cells of triploid N 722 used for sex teachings of dried yeast and obtained by crossing the French race FV-12 and an adenine-dependent mutant.

 The strain is stored in the Central Museum of Industrial Microorganisms under the number U-493.

 Comparative physiological and biochemical characteristics of the hybrid yeast strain N 5 of the production culture "Moskovskaya-23" (M-23) and the original strains of Yabloko and N 722 are given in table 1.

 From the data of Table 1 it can be seen that the new yeast strain N 5, in comparison with the production race M-23, Yabloko and N 722 strains, has a higher enzymatic (zymase 46 min, maltase 90 min) and generative activities (0.318 modulo growth ), low osmosis sensitivity (2 min), tolerates the presence in the environment of various organic acids, which tend to accumulate during the production of liquid yeast.

PRI me R. 1 loop with jamb museum culture hybrid N 5 is introduced into a test tube with 10 ml of 1 N, was incubated at 32 ^{° C} for 18-20 hours, then subjected to successive cultivation of yeast with gradual increase in volume from 100 ml to 1 liter of the medium under the same parameters.

 A 24-hour culture in a volume of 1 liter is transferred to the infusion, fermented with thermophilic lactic acid bacteria of the species Lactobacillus delfriickii, strain 30-1.

1 kg of wheat flour of grade II brewed 2.5 liters of water at a temperature of 90 ± 3 ^o C, to make welding hydrolyzate 0.25 kg of apple powder, 0.5 kg of inactivated biomass compressed baker's yeast, the mixture was cooled to 50 ± 2 ^{° C} and add a solution of hydrolytic enzyme preparations (Amilorizin P10x and Glucoamylase purified at the rate of 0.03% and 0.3% by weight of the flour in the tea leaves). The resulting flour is subjected to saccharification welding for 1 hour at 50 ± 2 ^{° C,} then add 0.5 L of pure 24-hour culture of thermophilic ICD, strain 30-1, previously grown on malt wort with crushing density 12 ^o Vlg. Duration of the fermentation step I 18-20 hours at a temperature of 50 ± 2 ° ^C. The final volume of 5 kg to 20 kg stage II wheat flour grade II brewed 30 liters of water at a temperature of 90 ± 2 ^{° C,} cooled to 50 ± 2 ^{° C,} making a solution of enzyme preparations in the amount of 0.5 liters, maintained at ^about 50 ± 2 C for 1 h, added to 50 kg of fermented tea leaves preceding stage are grown for 6-7 hours at 50 ± 2 ° ^C. in step III 120 kg brew 180 liters of water at a temperature of 90 ± 3 ° ^C, cooled to 50 ± 2 ° ^C, make 1 liter of solution of enzyme preparations, saccharified 1 hour at 50 ± 2 ^o C, is added 30 kg Coll vashennoy welding step II, maintained at 50 ± 2 ^{° C} for 6-7 hours. The total amount of 330 kg of fermented tea leaves, I and stage II is carried out in the laboratory and under production conditions III.

Next, a pure culture of yeast hybrid strain N 5 is transferred to saccharified tea leaves. For this, 1 liter of hybrid N 5 is added to a mixture of 4.5 kg of enriched and saccharified flour tea leaves and 0.5 kg of fermented tea leaves, the preparation of which is described above. Grow 15-17 hours at 30 ± 2 ^about C. The total volume of yeast 5 kg Then carry out the accumulation of liquid yeast with a sequential increase in the number of enriched and saccharified flour brewing in 2 times based on the introduction of yeast obtained in the previous stage, 10% The final volume of liquid yeast 500 kg

 In the process of elimination of liquid yeast on strain N 5, observations were made of the lifting force, number of cells and acidity compared to the Moskovskaya-23 race and hybrid N 512 (see table 2).

 Thus, liquid yeast prepared on the proposed hybrid strain N 5, in comparison with the known strains have better lifting force and increased reproduction energy.

Claims (1)

 The diploid hybrid strain of yeast Saccharomyces cerevisiae N 5 (stored at the Central Museum of Industrial Microorganisms under the number U-493) used for the production of liquid yeast.

Images