Main challenges in omega-3 enrichment
The increase in the demand for low-fat or fat-free products, together with the rising number of studies that show the beneficial health effects of omega-3 fatty acids, have led to the development of different techniques that allow the enrichment of non-fat foods and beverages with this PUFA. However, the main difficulties for the enrichment of non-fat food products and beverages are due to low water-solubility of omega-3 fatty acids and their high sensitivity to oxidation.
Because omega-3 fatty acids are highly unsaturated, they are very sensitive to autooxidation. Factors affecting the oxidation rates include fatty acid composition, storage conditions and physical state. Autooxidation of long chain PUFAs may cause the formation of oxidation products that apart from having a negative effect on the sensory characteristics of the final food products, may even result toxic to animals and humans. Therefore, potential vehicles for the delivery of omega-3 PUFAs should protect this sensitive nutraceutical from oxidation.
Moreover, omega-3 fatty acids are very hydrophobic and practically insoluble in water, even in the free fatty acid form. In fact, depending on the conditions, these fatty acids may self-assembles into micelles, aggregate in the forms of vesicles and oil droplets that may even lead to phase separation. This, evidently, presents an important limitation for the enrichment of aqueous food matrixes, such as clear beverages.
