As the Omega-3 fatty acids in fish oil have been identified as a substance of interest efforts have been made to economically develop more and more concentrated forms. This has been done to give formulators the greatest amount of flexibility possible; in essence to create the ability to deliver the highest does of the fatty acids with the least amount of additive. To this end fish oils have been fractionated through molecular distillation in order to concentrate the fatty acids: EPA and DHA. Since triglycerides do not fractionate well, they are first transformed to ethyl esters and then fractionated. Subsequent manipulation of the distillation conditions results in final products of varying EPA and DHA ratios. Some believe that the molecular distillation process results in a “cleaner” source of omega-3 fatty acids and so the term “pharmaceutical grade” fish oil has been coined to describe these materials. Ethyl Ester Concentrates tend to be of a lower viscosity than regular fish oils and color can vary with fatty acid concentrations.
