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Spray drying is appropriate for the preservation of halophilic microorganisms due to the nature of these microorganisms, as they survive in adverse environmental conditions by being encapsulated in salt crystals. Artificial neural networks were in this study used to optimize practically significant spray-drying regimes of the C-carotenoids producer Halobacterium salinarum. Immediately after drying, the samples contained up to 54% halobacterial biomass and less than 5% moisture, and the level of preservation of carotenoids was 95-97%. The storage of biomass at 4 °C resulted in the gradual degradation of the carotenoids, which reached 58-64% in the best samples after 1 year. A comprehensive study of changes in halobacteria biomass after spray drying and the nature of the damage provided new data on the survival and preservation of cells and biologically active substances in the various spray-drying regimes and at different storage times.

Introduction. Obtaining protein and vitamin fodder is one of the urgent tasks that modern industrial biotechnology has to solve. Another task is a search of novel medium compositions for microbial fermentation that can lower production costs. Russian food industry produces a significant amount of sunflower seed processing byproducts every year. Sunflower meal is a promising source of sunflower protein isolate. The research objective was to develop a new technology for the production of Bacillus megaterium bacterial biomass for fodder purposes. Study objects and methods. The research featured a sunflower protein isolate, an enzyme complex Protex 7L, and a B. megaterium strain (VKPM B-3750). The carbohydrate content was determined using a modified Bertrand method. Amine nitrogen was studied using formol titration, the number of viable cells – by the Koch method, the content of amino acids – by capillary electrophoresis. Results and discussion. When processed with enzyme complexes, sunflower protein can be an alternative source of nitrogen for industrial fermentation. The study featured amino acid of sunflower protein isolate and enzymatic hydrolyzate obtained using Protex 7L. A comparative analysis of the content of amino acids in the hydrolyzate and the protein isolate showed that enzymatic hydrolysis can significantly increase the content of free amino acids in the medium available for microbial accumulation. The research proved that sunflower protein enzymatic hydrolyzate obtained using Protex 7L can be used to cultivate strains of B vitamins producers. Conclusion. Sunflower protein enzymatic hydrolyzate can be used as a nitrogen source for B vitamins producer fermentation and as an alternative to expensive meat peptone. The research involved technical and economic assessment of the B. megaterium fermentation on enzymatic hydrolysates of sunflower protein at a production capacity of 100 kg per year. The cost of the protein-vitamin supplement was calculated as 413 rubles per kg, while the market price could reach 826 rubles per kg. The payback period for capital expenditures was estimated at 1.5 years. Thus, replacing commercial meat peptone with sunflower protein enzymatic hydrolyzate obtained with Protex 7L reduced the cost of 1 kg of feed additive by three times without affecting B. megaterium. Overproduction of B vitamins by the B. megaterium strain on a medium containing sunflower protein hydrolyzate requires optimization of fermentation conditions.

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