Fish and fish by-products are the main natural source of omega-3 polyunsaturated fatty acids, especially
EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), both of them with a great importance in
the food and pharmaceutical industries. Comparing to conventional fish oil extraction processes such
as cold extraction, wet reduction or enzymatic extraction, supercritical fluid extraction with carbon dioxide
under moderate conditions (25 MPa and 313 K) may be useful for reducing fish oil oxidation, especially
when fish oil is rich in omega-3 such as salmon oil, and the amount of certain impurities, such
as some species of arsenic. Furthermore, taking profit of the advantages of supercritical carbon dioxide
as extractive solvent, a coupled extraction-fractionation process is proposed as a way to remove free fatty
acids and improve fish oil quality, alternatively to physical and chemical refining procedures.
