Methods of extraction, refining and concentration of fish oil as a source of omega-3 fatty acids

Abstract

Fish oil is an industrial product of high nutritional value because of its Omega-3 polyunsaturated fatty acids content, currently valued for their beneficial effects on health. Studies and advances made since year 2000 on fish oil extraction from several fish species, its refining and polyunsaturated fatty acids concentration are reviewed in this article. Extraction techniques range from conventional technologies such as wet pressing and extraction using solvents, to more recently proposed technologies such as supercritical fluids and fish silage. Moreover, although refining is performed by traditional methods, there are new technologies with potential to be applied on fish oil. On the other hand, interest in omega-3 polyunsaturated fatty acids concentration has increased and several techniques such as winterization, enzymatic methods, supercritical fluids fractionation, complex formation with urea, fractionation by chromatographic methods and concentration by membranes have been proposed. The information collected indicates a trend to combine different conventional and emerging technologies to improve product yields and purity.