Comparative analysis of fatty acid composition of rainbow trout muscle tissue of various origins

A comparative analysis of the fatty acid composition of the muscle tissue of rainbow trout grown in fish farming conditions in Turkey and Russia (Republic of North Ossetia) using Russian mixed feed is presented. The total fat content and polyunsaturated fatty acid (PUFA) profile were evaluated. Analysis of the fatty acid composition of trout muscle tissue showed that the Turkish sample contains 1.25 times more docosahexaenoic acid, while the Russian sample contains 1.22 times more eicosapentaenoic acid. In terms of the total content of these fatty acids, Turkish trout slightly surpasses Russian trout. Thus, both products are comparable in terms of total nutritional value in the context of omega-3 PUFA, but have different functional orientation. The results indicate a direct dependence of the nutritional value of fish on the composition of feed and indicate the need to optimize the formulations of Russian feed to increase their competitiveness. Mixed feed for trout contains a mixture of fish oil and rapeseed oil, which is characterized by a high content of unsaturated fatty acids – up to 90%, while the proportion of linolenic acid can reach 12%. Polyunsaturated fatty acids of the omega-6 family in animal feed are mainly represented by linoleic acid and arachidonic acid. The proportion of linoleic acid reaches 96.8%. The total content of dosapentaenoic, docosahexaenoic and eicosapentaenoic fatty acids was 16.8%. This indicator is slightly lower than the recommended level of omega-3 PUFA in trout feed, which is 20% of the total of all fatty acids. To optimize the fatty acid profile of fish products, it is advisable for Russian feed manufacturers to consider the possibility of including in their formulations, in addition to traditional sources of essential PUFA, such as fish oil and vegetable oils, and modern highly effective feed additives from microalgae.