Molecular distillation removes impurities (heavy metals, dioxins, etc), saturated fats, and other undesirable organic compounds, leaving behind only the key beneficial components of the fish oil. It is a gentle distillation process with exceptionally low heat residence time, and is performed in a vacuum to further reduce the heat requirement. Flash distillation accomplishes the same thing as molecular distillation, but utilizes steam rather than a vacuum.
CO2 extraction or fractionation starts with oil that has previously undergone either molecular distillation or flash distillation to remove impurities. It uses a combination of pressure and heat to concentrate the amount of omega-3s (EPA and/or DHA) in the oil, extracting the ethyl esters from the fish oil in order to increase their concentration.
Nordic Naturals does not use CO2 extraction because it has not been shown to provide a superior quality product. Independent lab results consistently show that our processing techniques deliver oils of exceptional quality and freshness. Certificates of Analysis are available on our website; simply enter your lot number to view the certificate for your specific bottle.