by Caleb Summeril
Omega-3 Sources and Extraction Methods
Traditionally known as a fish oil supplement, the current marketplace offers Omega-3s from many other sources. Both plant and animal based products are now widely available with many varying in source and/or method of extraction. The benefits of incorporating Omega-3 into the diet are widely known and with so many available options, it is now easier than ever to find specific products to match individual preference.
The majority of Omega-3 oils derived from animal products come from fish. Cold water finfish are usually used to source the oil due to high levels of EPA and DHA (two beneficial fatty acids) found within their bodies. Salmon, herring, mackerel, anchovies and sardines are all common species used to source fish oil supplements.
Plant based sources of Omega-3s are also available with chia seeds, algal oil, Brussel sprouts, hemp seeds, flax seeds, walnuts and perilla oil being some of the best.  Algal oil (oil derived from marine algae) is one of the only plant sources to provide both EPA and DHA. Most other plant sources provide only ALA, which is beneficial but needs to be converted to EPA and DHA within the body for the health benefits to be seen.
Fish oils are traditionally extracted by multiple methods including hydraulic pressing, solvent extraction and heat extraction. These methods lead to high temperatures which can potentially degrade quality. New methods include supercritical fluid extraction, enzyme extraction, microwave-assisted extraction and ultrasound-assisted extraction.
Plant based Omega-3 sources are converted into products via less labor intensive, and more environmentally friendly methods, including water extraction and enzyme extraction.
Alves Marins, Dulce, et al. Alternative Sources of n-3 Long-Chain Polyunsaturated Fatty Acids in Marine Microalgae. Mar Drugs. 2013 Jul; 11(7): 2259-2281.