Siscowet Lake Trout high in omega-3 fatty acid content
Michigan Sea Grant and fishery managers around Lake Superior are exploring the feasibility of a fishery for siscowet lake trout as a good source for of omega-3 fish oil for the nutraceutical industry.
Michigan Sea Grant hosted a presentation on “Siscowet Lake Trout Oil Rendering” at the Lake Superior Technical Committee (LSTC) meeting in Duluth, MN and at the Michigan Fish Producers Association Annual Conference in Traverse City in January 2012. Because of the high fatty acid content of Lake Superior siscowet lake trout, Michigan Sea Grant and fishery managers around Lake Superior are exploring the feasibility of a fishery for this species, which could supply fish for an oil rending facility to produce fish oil for the nutraceutical industry. Paul Addis, Professor Emeritus-University of Minnesota, is conducting the study for Michigan Sea Grant and discussed his assessment of siscowet lake trout oil content at the LSTC meeting and at the Michigan Fish Producers Association Annual Conference.
Fatty acids in fish oil are considered essential fatty acids. They can break down differently in the body and the by-products can influence blood clotting. Researchers believe that fish oils break down into healthier by-products than fatty acids from vegetable sources. There are a number of barriers to fish oil arriving on the market, including a number of misconceptions that are deliberately advocated (e.g., claims that contaminants are present). These are removed when processing the fish oil. Some claim that only saltwater fish have the omega-3 fatty acids. Not true, many of our freshwater species also have these important oils.
There are important nutritional benefits to fish oils including reducing platelet activity and clotting, which reduces the risk of heart attacks and stroke. There are a number of types of fatty acids, some of which need to come from plant sources (linoleic and linolenic acids) that cannot be produced by animals and must come from the diet. Many researchers believe that the North American diet is too high in omega-6 (vegetable oils) and too low in omega-3 fatty acids.
Siscowet lake trout oil has fairly high docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA) levels, with reasonable levels of eicosapentaenoic acid (EPA). There are also important human, animal and fertilizer uses for the product. Addis believes there will be a continued increase in demand as supply is slowly decreasing contributing to price fluctuation. Siscowet lake trout are a good source of omega-3 and EPA and DHA – better than most other fish. Most fish oil is produced as a by-product of fishmeal production using a steam heated cooking process to release oil. The oil is then separated and refined prior to use. A five-pound fish, for example, with 40% oil will result in 1 pound of oil after refining.
Past research by Addis at the University of Minnesota has determined that a number of Lake Superior fish species are excellent sources of omega-3 fatty acids. Lake Superior fish, with the exception of burbot, easily exceed the omega-3 content of halibut. The omega-3 content of chub, lake herring, lake whitefish, lean lake trout and siscowet lake trout exceeds the omega-3 content of Chinook salmon, which is one of the best saltwater sources of omega-3 fatty acids. Another attribute of the Lake Superior fish is the high content of monounsaturated oil, the type of fatty acid found in olive and canola oils. Recent medical research indicates that monounsaturated oils are more effective than N-6 polyunsaturated oils in lowering blood cholesterol.