EVALUATION OF FOOD AND FUNCTIONAL-TECHNOLOGICAL PROPERTIES OF COLLAGEN HYDROLYSATES FROM SARDINELLA SCALES

The aim of research is to determine the nutritional and functional-technological properties of fish scale hydrolysates for the production of food additives and their use in food systems. The studies were carried out on the scales of Moroccan sardinella (Sardinella aurita) using enzymatic and thermal hydrolysis methods. As a result of hydrolysis, water-soluble and water-insoluble fractions were obtained, which were dried and ground. The organoleptic properties, chemical composition, amino acid composition, biological value, molecular-fractional composition, elemental composition, water-holding, water-binding and fat-binding capacities, emulsifying properties were determined in the obtained powders. The content of protein substances in the scales, water-soluble and water-insoluble hydrolysates was 30.3 %; 81.9–87.1 %; 59.8–62.5 %, respectively; mineral substances – 22.2 %; 5.3–6.8 %; 29.3–31.4 %. Water-soluble supplements were found to contain all essential amino acids, with a protein biological value of 59.9 %. Water-insoluble supplements contained significantly fewer amino acids, with a protein biological value of 10.7 %. The mineral content of the insoluble fractions of hydrolysates ranged from 29.3–31.4 %, with calcium, chlorine, potassium, and sulfur being the most abundant. Water-soluble additives produced by all hydrolysis methods are concentrates of low-molecular-weight active peptides with an MM of less than 10 kDa (53.3–97.7 %). These hydrolysates, regardless of the production method, exhibited the best functional and technological properties, which determine their structure-forming properties. Water-soluble hydrolysates are recommended for use in food products as a source of biologically active peptides and collagen-based amino acids in specialized products for athletes. Water-insoluble hydrolysates are suitable for use in osteotropic dietary supplements as a source of high-molecular-weight collagen proteins and minerals. Both additives have been successfully tested in the formulations of protein bars and gelatinized products intended for sports nutrition.