Biocompatibility of micronutrients to obtain enriched food ingredients

The aim of the study is to investigate the compatibility of trace elements for the possibility of combined enrichment of yeast with iron and copper. The objects of the study were a strain of baker's yeast from the collection of microorganisms of the AllRussian Research Institute of Food Biotechnology, Laboratory of Baker's Yeast Biotechnology, and salts of iron, copper and manganese sources of trace elements. Yeast was cultured on a microbiological shaker at a rotation speed of 220 rpm in 750 cm3 Erlenmeyer flasks with 75.0 cm3 of a standard medium with a dry matter content of 8 % for 18 hours at a temperature of 30 °C. The quantitative content of nitrogenous substances in yeast biomass was determined by the Kjeldahl method according to GOST 13496.42019. Biomass accumulation was studied by the weight control method after cultivation, separating the solid and liquid fractions by centrifugation. Separation of biomass into solid and liquid fractions was carried out on a laboratory centrifuge OPM16 for 12 minutes at a rotation speed of 8000 rpm. Microelement composition (iron and copper) was determined by atomic absorption spectrometry with electrothermal atomization on a KVANTZ.ETA device. Comparative studies of the methods of fortification of the selected strain S. cerevisiae Y581 c were carried out, confirming the practical possibility of combined enrichment of yeast with iron and copper: 1 – during yeast cultivation; 2 – enzymatic lysates of inactivated cells, with obtaining enriched products with various functional and technological properties and target areas of their application. Rational dosages of microelements in nutrient media for culturing the selected strain (50 mg iron, 2.5 mg copper and 5.0 mg manganese per 100 cm3) were established, allowing to achieve the percentage of iron incorporation (90.7 %) and copper (72.5 %) and an increase in the level of protein synthesis by 15.5 %. Positive dynamics of increasing the degree of enrichment with microelements during fortification of enzymatic lysates of inactivated yeast was revealed and rational conditions were established that provide the highest level of microelement content (Fe + Cu) in the target product. The results of the fractional composition of the yeast fermentolysate confirmed a significant increase in the content of free amino acids, lowmolecular peptides and soluble carbohydrates in bioavailable form. A basic block diagram for obtaining yeast fermentolysate with iron and copper has been developed.