SOWW-1: Soft Winter Wheat Flour Reference Material for Trace Metals and other Constituents

SOWW-1 is a Reference Material prepared from enriched soft winter wheat flour. Reference and information quantity values are provided in the following tables for trace metals and other constituents. Reference values are equally weighted means of results from at least two analytical methods and/or laboratories. Uncertainties are expressed as a 95% confidence interval. All values are expressed on a dry-mass basis.

Table 1: Reference values for SOWW-1

Element Mass fraction, mg/kg
Calcium 240 ± 23
Magnesium 214 ± 16
Manganese 5.4 ± 0.6
phosphorus 1080 ± 60
Potassium 1480 ± 210
Sulfur 1260 ± 190

Table 2: Information values for SOWW-1

Element Mass fraction, mg/kg
Aluminium 2.3
Barium 1
Boron 0.1
Cadmium 0.03
Chlorine 640
Chromium 0.032
Copper 1.2
Fluorine 0.04
Iron 29
Molybdenum 0.29
Selenium 0.076
Nitrogen 17 600
Sodium 7
Vanadium 0.03
Zinc 5.8

Intended use

This Reference Material (RM) is intended for use in evaluating analytical methods and instruments used for the determination of major, minor, and trace constituent elements in flour and other similar food, agricultural, and biological materials. A minimum sample mass of 500 mg is recommended.

This material is intended for laboratory use, not for human consumption.


Original uncertainty estimates for RM 8438 were verified at NRC and were retained in this report. As stated in the RM 8438 report [1], uncertainties are imprecision estimates expressed either as a 95% confidence interval, based on a sample weight of at least 500 mg. These uncertainties, based on between-method and laboratory, between-unit and within-unit estimates of variances, include measures of analytical method and laboratory imprecisions and biases and material inhomogeneity.

Date of Issue: September 2015
Date of Expiry: September 2025
Revised: March 2016 (editorial update)

Date modified: