Elemental Analysis of Amaranth, Chia, Sesame, Linen, and Quinoa Seeds by ICP-OES: Assessment of Classification by Chemometrics

Abstract

In this work, 26 elements (Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cs, Cu, Ga, Fe, K, Mg, Mn, Na, P, Pb, Rb, Se, Si, Sr, Ti, V, and Zn) were analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES) in seed samples: amaranth, chia, sesame, linen, and quinoa. Elemental analysis showed the presence of toxic elements (As, Cd, and Pb), as well as high mineral content (Fe, Na, P, K, and Mg): The concentrations of toxic elements were below the permissible limits by the WHO. Chemometrics was performed by cluster analysis (CA), principal component analysis (PCA), and partial least squares discriminant analysis (PLS-DA). In all cases, a correct classification of each type of seed was obtained. The combination of elemental analysis (major, minor, and toxic elements) and chemometrics was useful to determine nutritional quality in the studied seeds, as well as to classify them according to the botanical origin. For that, this method can be useful for the analysis of raw material as quality control in food factories and government control labs.