Matrix Extension Validation of AOCS Ce 2c‐11 for Omega‐3 Polyunsaturated Fatty Acids in Conventional Foods and Dietary Supplements Containing Added Marine Oil

Abstract

AbstractMarine oils are commonly added to conventional foods and dietary supplements to enhance their contents of omega‐3 polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA; 20:5n‐3) and docosahexaenoic acid (DHA; 22:6n‐3), which have been associated with numerous potential health benefits. This study compared American Oil Chemists’ Society (AOCS) Official Methods Ce 2b‐11 and Ce 2c‐11 for determining EPA and DHA in foods and dietary supplements and found that AOCS Ce 2c‐11 produces significantly higher analyzed values, which could be attributed to a more comprehensive breakdown of the sample matrix and derivatization of fatty acids. Our subsequent food matrix extension validation of AOCS Ce 2c‐11 demonstrated that the method produces true, accurate, sensitive, and precise determinations of EPA, DHA, and total omega‐3 PUFA in foods and dietary supplements containing added marine oil, including those formulated with emulsified and microencapsulated oils. The method detection limits for EPA and DHA were 0.012 ± 0.002 and 0.011 ± 0.003 mg g−1, respectively (means ± SD). The analyzed contents of EPA (1.26–386 mg serving−1), DHA (1.37–563 mg serving−1), and total omega‐3 PUFA (2.69–1270 mg serving−1) were reported for 27 conventional food and dietary supplement products. Eighteen products declared contents of DHA, EPA + DHA, or total omega‐3 PUFA on product labels, and the analyzed contents of those fatty acids varied from 95 to 162% of label declarations for all but two of the products.