Value Assignment of Nutrient Concentrations in Five Standard Reference Materials and Six Reference Materials

Abstract

A number of food-matrix reference materials (RMs) are available from the National Institute of Standards and Technology (NIST) and from Agriculture Canada through NIST. Most of these materials were originally value-assigned for their elemental composition (major, minor, and trace elements), but no additional nutritional information was provided. Two of the materials were certified for selected organic constituents. Ten of these materials (Standard Reference Material® [SRM] 1563 Cholesterol and Fat-Soluble Vitamins in Coconut Oil [Natural and Fortified], SRM 1566b Oyster Tissue, SRM 1570a Spinach Leaves, SRM 1974a Organics in Mussel Tissue (Mytilus edulis), RM 8415 Whole Egg Powder, RM 8418 Wheat Gluten, RM 8432 Corn Starch, RM 8433 Corn Bran, RM 8435 Whole Milk Powder, and RM 8436 Durum Wheat Flour) were recently distributed by NIST to 4 laboratories with expertise in food analysis for the measurement of proximates (solids, fat, protein, etc.), calories, and total dietary fiber, as appropriate. SRM 1846 Infant Formula was distributed as a quality control sample for the proximates and for analysis for individual fatty acids. Two of the materials (Whole Egg Powder and Whole Milk Powder) were distributed in an earlier interlaboratory comparison exercise in which they were analyzed for several vitamins. Value assignment of analyte concentrations in these 11 SRMs and RMs, based on analyses by the collaborating laboratories, is described in this paper. These materials are intended primarily for validation of analytical methods for the measurement of nutrients in foods of similar composition (based on AOAC INTERNATIONAL's fat–protein–carbohydrate triangle). They may also be used as “primary control materials” in the value assignment of in-house control materials of similar composition. The addition of proximate information for 10 existing reference materials means that RMs are now available from NIST with assigned values for proximates in 6 of the 9 sectors of the AOAC triangle. Five of these materials have values assigned for total dietary fiber—the first such information provided for materials available from NIST.

Effects of Boron Deficiency on Geranium Grown under Different Nonphotoinhibitory Light Levels

“…A quality control was run every 10 samples and if any element was determined to be more than 10% higher or lower than the standard value, the instrument was recalibrated. Tomato (Solanum lycopersicum L.) standards (NIST reference material 1573; National Institute of Standards and Technology, Gaithersburg, MD) (Sharpless and Gill, 2000) were compared every 20 samples and tomato and spinach (Spinacia oleracea L.) standards (NIST reference material 1570a) (Sharpless and Gill, 2000) were compared every 40 samples.…”

Alleviation of Copper Toxicity in Arabidopsis thaliana by Silicon Addition to Hydroponic Solutions

“…A quality control was run every 10 samples and if any element was determined to be more than 10% higher or lower than the standard value, the instrument was recalibrated. Tomato (Solanum lycopersicum L.) standards [National Institute of Standards and Technology (NIST, Gaithersburg, MD) reference material 1573 (Sharpless and Gill, 2000)] were compared every 20 samples and tomato and spinach (Spinacia oleracea L.) standards [NIST reference material 1570a (Sharpless and Gill, 2000)] were compared every 40 samples. Total N was analyzed with a total carbonhydrogen-nitrogen analyzer (model 2400; Perkin-Elmer, Waltham, MA).…”

Liquid Chromatographic Analysis of Riboflavin Vitamers in Foods Using Fluorescence Detection

“…Additionally, the method is simple because the vitamers are isocratically eluted, while most published methods used gradient elution ( 4 , 13−16 , 18−20 , 22 ). The use of reference materials is invaluable for assessing method accuracy; however, only some recent papers have used these materials to prove the accuracy of the methods ( − ) . The present study includes an original application of the use of two certified reference materials as a validation method for B 2 vitamers analysis.…”