Chemometrics for Discriminating the Geographical Origin of Korean and Imported Wheat Flour

Abstract

Consumers consider geographical origin an important factor when choosing a product. Therefore, research is continuously conducted to determine the country of origin of products such as wheat. In this study, inorganic elements were used to identify Korean and imported wheat flour using inductively coupled plasma (ICP) analysis. Chemometrics was employed to suggest a method for determining the country of origin, which included principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and orthogonal partial least squares discriminant analysis (OPLS-DA). In PLS-DA and OPLS-DA, 21 and 19 elements were investigated to influence the determination of geographical origin. The elements with the greatest discriminatory power were 88Sr and Fe. OPLS-DA had the highest Q2 and R2 scores, clearly differentiating Korean and imported wheat flour. In a heatmap, the inorganic element content of each flour group was observed, and canonical discriminant analysis (CDA) confirmed the country of origin with 100% accuracy. CDA showed 98% accuracy with only one imported sample error in the validation set. Furthermore, this work can inform method selection for the country of origin determination of other product types.