A retail market study of organic and conventional potatoes (Solanum tuberosum): mineral content and nutritional implications

Abstract

Whether or not all foods marketed to consumers as organic meet specified standards for use of that descriptor, or are nutritionally different from conventional foods, is uncertain. In a retail market study in a Western US metropolitan area, differences in mineral composition between conventional potatoes and those marketed as organic were analysed. Potatoes marketed as organic had more copper and magnesium (p < 0.0001), less iron (p < 0.0001) and sodium (p < 0.02), and the same concentration of calcium, potassium and zinc as conventional potatoes. Comparison of individual mineral concentrations between foodstuffs sold as organic or conventional is unlikely to establish a chemical fingerprint to objectively distinguish between organic and conventional produce, but more sophisticated chemometric analysis of multi-element fingerprints holds promise of doing so. Although statistically significant, these differences would only minimally affect total dietary intake of these minerals and be unlikely to result in measurable health benefits.

Keywords::

• Potatoes
• organic food
• mineral content
• retail market study

Acknowledgements

The authors gratefully acknowledge the capable technical assistance of Mr Michael Wood, Department of Chemistry and Biochemistry, Brigham Young University, in the operation of the ICP-OES for sample analysis.

Declaration of interest: This work was supported by a grant from the Office of Research and Creative Work, Brigham Young University. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.