Stability and stabilization of omega-3 oils: A review

Background: Omega-3 oils are rich sources of essential fatty acids and play a key role in biological functions in the body and sensory attributes in food systems. The high content of long chain polyunsaturated fatty acids leads to high vulnerability of omega-3 oils to oxidation, and thus causes deterioration of their nutritional values and biological functions. Stabilization technologies continue to be important research topics for both academia and industry. Scope and approach: We have reviewed traditional and newly-developed stabilization technologies applied to omega-3 oils with proven efficacy in preventing or inhibiting lipid oxidation. These methods were developed to target one or more factors that determine oxidative stability of omega-3 oils. Key findings and conclusions: The effective traditional stabilization technologies, including the removal of oxygen and catalysts, and the addition of antioxidants should be further studied for their safety, synergistic effect and as affected by packaging material. Newly-developed stabilization technologies, such as blending, randomization and enzyme-catalyzed conversion to omega-3 phenolic antioxidants provide new approach not only to stabilize omega-3 oils, but some also provide new omega-3 oil based antioxidants as nutraceutical products. The conversion rate and position specificity of structural modifications and incorporation of antioxidants as well as safety of newly prepared compounds for human consumption require future attention. Emulsion and encapsulation technologies, especially those involved in micro/nano-technologies should also be promoted to protect omega-3 oils due to the convenience of release control, improved stability and bioavailability, but high processing efficiency and low cost are required for large scale production.