Geochemical markers of Ilex paraguariensis determined by PIXE

The knowledge of the geographical origin of food is related to the consumer’s safety and usually aggregates market value to the product. One way to identify the geographical origin of foodstuff is through the determination of geochemical markers. The aim of this work is to determine the elemental composition of the mate tealeaves (Ilex paraguariensis) and identify possible elements which could be considered as geochemical markers. To that end, packaged tealeaves from nine different South American regions were analyzed by Particle-Induced X-Ray Emission. Moreover, tealeaves of a particular brand manufactured and packed in Brazil and commercialized in Brazil and Uruguay were analyzed as well. Results showed that Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr and Ba are present in the mate tealeaves. Considering the average concentrations of the elements from each region, there are significant differences among the regions for all elements but S. Multivariate statistical analysis indicates that the variability of the elements could be used to characterize the provenance of Ilex paraguariensis. Some elements such as Mg, Cu, Sr, Mn and Ni are correlated, which could be used to identify the geographical origin of this product.