Yerba mate is traditionally consumed in South America, and it has recently been highly publicized for its health benefits; however, consumers have felt differences in bitterness even in products of the same brand. The aim of this research was to compare the intensity of bitterness in native leaves and in cultivated leaves from 5- and 15-year-old trees, and determine the content of caffeine, reducing sugars and tannin in yerba mate leaves to explain their influence in bitterness. Bitterness was associated with age and cultivation of the plant, both of which can contribute to different blends of yerba mate. Sensory analysis revealed a significant difference between 5-year-old cultivated leaves and leaves from native trees and that bitterness decreases according to the age of the plant. Chemical analysis showed that caffeine and sugar content have no influence on its bitterness. However, tannin concentration is higher in younger plants, which are considered more bitter than older plants.


Consumption of yerba mate (maté) is a social habit in South America; it is consumed as an infusion of the Ilex paraguariensis leaves. The increase of maté consumption has raised the need for the cultivation of this plant in monoculture (cultivated trees) and also the interest of the industries to standardize the flavor of beverages made with yerba mate. Bitterness is the principal sensorial difference between several maté teas, chimarrão and tereré. There are several practical observations on the relation between the age of the plant and bitter taste. Nowadays, it is common to use yerba mate leaves from cultivated plants, which are considered more bitter than native plants. Tannin, caffeine and sugar are also related to the taste characteristics of yerba mate. In this work, native and cultivated yerba mate leaves from three different farms were used with the objective of explaining those relations with the taste of yerba mate.