Rapid Assessment of Extractability of Macronutrients from Yerba Mate (Illex paraguariensis) Leaves Based on Laser-Induced Breakdown Spectroscopy

Abstract

Leaves of yerba mate plant (Ilex paraguariensis) have a wealth of nutrients, ingested by people who drink them in the hot water infusion popularly known as mate. In the present work, the laser-induced breakdown spectroscopy (LIBS) technique was applied for the first time to analysis of the extractability of macronutrients, including Mg, Ca, Na, and K, in commercial samples of yerbamate. Powdered samples from leaves’ material were used to simulate the infusion process in thelaboratory. To carry out LIBS analysis, the emission spectra were measured before and after theinfusion from the samples prepared in pellets. The spectral data were processed and analyzed by aspecially designed algorithm. A coefficient of extractability was calculated for each of the investigatedmacronutrients in the range 34–76%, showing a good correlation with the corresponding elementalconcentrations leached into the water infusion, determined by Atomic Absorption Spectroscopy. Theobtained results demonstrated the feasibility of our approach for the rapid analysis of extractablemacronutrients present in yerba mate leaves.