Evolution of reference materials for the determination of organic nutrients in food and dietary supplements—a critical review

Abstract

For over 40 years, food-matrix certified reference materials (CRMs) have been available for determination of trace element content, and a wide variety of materials are available from most producers of CRMs. However, the availability of food-matrix CRMs for organic nutrients has been more limited. The European Commission (EC) Bureau Communautaire de Référence (BCR) and the National Institute of Standards and Technology (NIST) introduced food-matrix CRMs with values assigned for vitamins and other organic nutrients such as fatty acids and carotenoids in the 1990s. The number of organic nutrients for which values were assigned has increased significantly in the past decade, and the approach and analytical methods used for assignment of the certified values have also evolved. Recently, dietary supplement-matrix CRMs such as multivitamin tablets with values assigned for vitamins and carotenoids, and fish and plant oils with values assigned for fatty acids have appeared. The development, evolution, and improvement of food- and dietary supplement-matrix CRMs for determination of vitamins, carotenoids, and fatty acids are described, with emphasis on CRMs made available in the past 10 years. Recent food and dietary supplement CRMs for the determination of organic nutrients include infant formula, multivitamin tablets, milk and egg powders, breakfast cereal, meat homogenate, blueberries, soy flour, fish and plant oils, dry cat food, and protein drink powder. Many of these food- and supplement-matrix CRMs have values assigned for over 80 organic and inorganic nutrients, toxic elements, proximates, and contaminants. The review provides a critical assessment of the challenges and evolving improvements in the production and the analytical methods used for value assignment of these CRMs. The current status and future needs for additional food- and dietary supplement-matrix CRMs for organic nutrients are also discussed.

The Importance of Reference Materials and Method Validation for Advancing Research on the Health Effects of Dietary Supplements and Other Natural Products

“…The determination of fatty acids using GC with flame ionization detection (FID) and GC-MS are relatively mature measurement techniques in food and dietary supplement analysis, and as a result, matrix-based CRMs to support these analyses have been available since the late 1990's ( 75 ). With the importance of fatty acids in nutrition studies, particularly omega-3 and omega-6 compounds, SRM 3274 Botanical Oils Containing Omega-3 and Omega-6 Fatty Acids and SRM 3275 Omega-3 and Omega-6 Fatty Acids in Fish Oil were developed as suites of four and three different mixtures of botanical and fish oils, respectively, to provide different levels and different ratios of the individual fatty acids.…”

“…Adapted and reprinted with permission from Springer, Anal. Bioanal.Chem ., Wise and Phillips ( 75 ).…”

From urban dust and marine sediment to Ginkgo biloba and human serum—a top ten list of Standard Reference Materials (SRMs)

“…In the mid-1990s NIST initiated a program to develop foodmatrix SRMs for the determination of vitamins and organic nutrients [43]. With the issuance of SRM 1846 Infant Formula in 1996, NIST started the most successful series of foodmatrix SRMs.…”

Total and Free Fatty Acids Analysis in Milk and Dairy Fat

“…Finally, it should also be noted that certified reference material (CRM) is recently available in the case of some individual TFA. This is SRM 1549a Whole Milk Powder, provided by NIST [109]. However, to the best of our knowledge, it has not yet been employed on the subject we are dealing with.…”