TO THE QUESTION OF BIOLOGICAL VALUE OF FISH OIL EXTRACTED FROM THE INTERNAL ORGANS OF COMMODITY STURGEON
The study solved the problem of rational use of fat-containing wastes as secondary raw material, which prevents their disposal at low price for transmission to the forage production. The aim of the work was to study the physical and chemical indicators of quality and biological value of fish oils extracted from sediments on the digestive organs of commodity sturgeon grown in the fish farms of the Astrakhan region. The objects of the study were: the fat deposits on the digestive organs of frozen commodity sturgeon; fish oil derived from them; extract of carotenoids from crust-included raw materials of crayfish. Fat deposits of commodity sturgeon were kept at a temperature not higher than -18 °C for 2 months. Other objects of the research are not subjected to long-term storage (more than two months). Frozen fat deposits of commodity sturgeon were exposed to defrosting using air way, thorough cleaning and were sent to the extraction of fish oil. It was found that the fat of commodity sturgeon (aquaculture facility) is deposited on the internal organs, which allows to harvest it as secondary raw material in processing by butchering. It was determined that the yield of the extraction of fish oil is 95.9 % of the amount contained in the feedstock, or 75.6 % of its mass. It was revealed that the collection and storage of fat deposits when butchering commodity sturgeon allow to extract food fish oil and then enrich it with biologically active substances of lipid origin containing polyunsaturated fatty acids on average 18.2 %. The metabolization effectiveness ratio was calculated, it amounted 0.99 for carotenoids of raw fat and 0.88 for enriched fat.