Вестник МГТУ, 2024, Т. 27, № 3.

Вестник МГТУ. 2024. Т. 27, № 3. С. 294-301. DOI: https://doi.org/10.21443/1560-9278-2024-27-3-294-301 Table 2. Quality indicators of a fish protein hydrolysate prototype Таблица 2. Показатели качества опытного образца рыбного белкового гидролизата The name of indicators Value Consistence Amorphous homogeneous powder Colour Light beige Aroma Typical for this type of product Active acidity, рН 6.75 ± 0.10 Moisture content, % 4.60 ± 0.26 Mass fraction of amine nitrogen, % 3.60 ± 0.09 Mass fraction of total nitrogen, % 12.97 ± 0.04 Mass fraction of fat, % 0.26 ± 0.02 Mass fraction of sodium chloride, % 2.70 ± 0.12 The experimental sample of fish protein hydrolysate received according to an optimized fermentation mode was used to make a culture medium in a control nutrient agar formulation, in which pancreatic fish meal hydrolysate is used as a nitrogen source. In the experimental culture medium, the pancreatic fishmeal hydrolysate was completely replaced by the experimental fish protein hydrolysate. As a control, we used "Nutrient agar for the cultivation of microorganisms, dry GRM". The formulations of the test and control culture media are presented in Table 3. Table 3. Recipes of culture media Таблица 3. Рецептуры питательных сред Name Amount, g (ml)/1 l of distilled water Nutrient agar for the cultivation of microorganisms, dry GRM Peptone for bacteriological culture media 12 Fishmeal Pancreatic Hydrolysate 12 Sodium chloride 6 Agar 10 Study culture medium based on a prototype fish protein hydrolysate Peptone for bacteriological culture media 12 Prototype fish protein hydrolysate 12 Sodium chloride 6 Agar 10 To control the quality of culture media, test microorganisms with stable characteristics was used. The prepared culture media were intended for counting the column of microorganisms. To control the quality of the prepared culture media, the coefficient of productivity of the culture medium was calculated. The productivity of the culture medium is the degree of growth of the target microorganism on the culture medium under certain conditions. Sowing test-cultures on the control and test media was performed by direct inoculation. Crops were incubated in a thermostat at a temperature of 37 ± 1 °C for 18-24 hours. Microorganisms were counted using GOST ISO 7218-2015 "Microbiology of food and animal feed. General requirements and guidance for microbiological examinations". Comparative characteristics of the growth performance of test microorganisms on the studied culture medium based on fish protein hydrolysate and nutrient agar GRM are presented in Table 4. Table 4. The growth form of test microorganisms on the studied culture medium based on fish protein hydrolysate and nutrient agar GRM Таблица 4. Сравнительная характеристика роста тест-микроорганизмов на исследуемой питательной среде на основе рыбного белкового гидролизата и питательном агаре ГРМ Tested culture media Dilution Staphylococcus aureus ATCC 25923 Salmonella enteriditis № 5765 Tested culture medium based on a prototype fish protein hydrolysate (Nc) 10-6 1.3x109 3.8x109 Nutrient agar for the cultivation of microorganisms, dry GRM (Nc) 10-6 1.3x109 3.5x109 297