Using isotopic characterization to identify the authenticity of Ilex paraguariensis brands marketed in southern Brazil

Authors: MARCHESE, JOSE - Federal University Of Technology - Parana; SCARIOTTO, SILVIA - Federal University Of Technology - Parana; ELLSWORTH, PATRICIA - Washington State University; STERNBERG, LEONEL - University Of Miami; Ellsworth, Patrick

Submitted to: Theoretical and Experimental Plant Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/23/2020
Publication Date: 8/14/2021
Citation: Marchese, J.A., Scariotto, S., Ellsworth, P.V., Sternberg, L.S., Ellsworth, P.Z. 2021. Using isotopic characterization to identify the authenticity of Ilex paraguariensis brands marketed in southern Brazil. Theoretical and Experimental Plant Physiology. 33:305-311. https://doi.org/10.1007/s40626-021-00206-0.
DOI: https://doi.org/10.1007/s40626-021-00206-0

Interpretive Summary: Yerba mate is an important tea in South America and is mostly harvested from a native tree species. Tea produced from the leaves of trees growing in the forest taste are less bitter than tea made from trees grown on plantations. To hide the bitter flavor of tea produced on plantations, sugar is added to the tea, which is illegal if concealed. Here a method using the carbon isotopic composition is used to distinguish between pure tea and tea adulterated with sucrose. Tea samples can be analyzed on a isotopic ratio mass spectrometer to determine if the sample has sugar contamination and the relative degree of contaminination. This method is precise and can be used effectively to detect fraud, providing a simple quality control method.

Technical Abstract: Yerba mate (Ilex paraguariensis) has both economic and cultural importance in South America. However, due to a lack of quality control during processing, adulteration can occur. The aim of the study was to detect sucrose contamination in yerba mate brands marketed in southern Brazil through isotopic characterization. For the experiment, fifteen brands from local grocery stores were analyzed; six samples of yerba mate derived from plants of different environments; five samples of other species of genus Ilex and Ligustrum japonicum, which commonly contaminate yerba mate. Values of d13C and d15N of the samples found that some marketed brands are contaminated by sucrose and potentially plant matter from other species. Isotopic characterization was found to be an efficient and reliable technique for identifying sucrose contamination in yerba mate and has great potential as quality control in the food industry.