Technology for obtaining essential fatty acids and protein hydrolyzate from by-products of slightly salted herring production

The technology for the rational use of collagen-containing waste, namely the skin from cutting slightly salted herring, is presented. The technology for obtaining oil containing polyunsaturated fatty acids and collagen hydrolyzate from by-products of production of preserves from slightly salted herring was developed. The rational parameters of hydrolysis in gentle conditions using electrochemically obtained catholytes have been determined and substantiated, which ensures waste-free processing of raw materials and the reduction of oxidized nutrients. The cryoconcentration method was used to concentrate essential acids. We studied the phase transitions of the obtained lipids in the temperature range from + 15 ° C to minus 40 ° C in a calcium chloride environment using a low-temperature refrigeration unit. The properties of 5 lipid fractions formed during lipid phase transitions have been identified and studied. The technology was applied to fatty raw materials - skin from cutting slightly salted herring into fillets. The physical and chemical properties of raw materials and finished products have been investigated. The mass yields of fish oil and collagen hydrolyzate have been determined. Comparative analysis of fatty acid composition of fish skin before and after electrochemical treatment has been carried out.