Secondary raw material of caviar production biopotential to obtain biologically valuable protein products

The purpose of the study is to substantiate the feasibility of using caviar production waste generated during salmon processing to obtain biologically valuable products with easily digestible protein by hydrothermal impact on secondary raw materials. Objectives: to substantiate the choice of waste generated during the punching of ovaries of Pacific salmon species as a valuable secondary raw material; to determine its biotechnological potential; to substantiate the expediency of using thermohydrolysis to obtain a biologically valuable protein product from caviar production waste. The material of the study is caviar processing by-products generated and collected during the punching of chum salmon ovaries in August 2022 at a fish processing plant located in the Khabarovsk Region. Sampling of raw materials and their preparation for analysis was carried out according to standard methods (GOST 31339-2006, GOST 7631-2008). The determination of the general chemical composition was carried out according to GOST 7636-85 Fish, marine mammals, marine invertebrates and products of their processing. Methods of Analysis. The amino acid composition of proteins was determined by capillary electrophoresis on a Kapel-105 device. The fractional composition of proteins was determined by high performance liquid chromatography with a Phenomenex column (Yarra 3uSEC = 2000). The investigated secondary raw materials have a high technological potential due to the presence of proteins in it, including collagen. The presence of collagen in caviar processing by-products is not constant and can vary depending on many factors. To obtain a biologically available protein, it was proposed to use barometric processing of secondary raw materials at a temperature of 130 °C. As a result of thermal hydrolysis, two fractions were obtained: water-soluble protein in the amount of 39.2 % of the total mass and sediment, which is a mixture of insoluble minerals and proteins. The water-soluble protein hydrolyzate was freeze-dried and analyzed for the presence of biologically valuable low molecular weight protein substances. The dry protein hydrolyzate contained 80.3 % protein and 30.61 % biologically valuable low molecular weight peptides with a molecular weight of less than 10 kDa.