EPA and DHA contents of encapsulated fish oil products

Seventeen brands of encapsulated fish oil or fish oil concentrate products, purchased during the period 1984–88 over the counter in the United States United Kingdom or Canada, were analyzed for their mg contents of eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids per g of capsule contents. The mg contents were determined with respect to methyl tricosanoate internal standard by gas liquid chromatography (GLC) on a SUPELCOWAX‐10 flexible fused silica capillary column. The alkyl ester and free fatty acid products showed very high levels of EPA (259–300 mg) and DHA (172–254 mg) whereas in the triglyceride oils EPA ranged from a low of 80 to a high of 250 mg, and DHA ranged from 78 to 156 mg, per g of capsule contents. The mg/g results indicate that the label claims for EPA and DHA for the majority of the products sampled are presented with reasonable accuracy.