Antioxidant Capacity, Phenolic Compounds, and Other Constituents of Cold and Hot Yerba Mate (Ilex paraguariensis) Infusions

Yerba mate beverage is prepared from <i>Ilex paraguariensis</i> grown in South America, and its popularity still is increasing. The aim of this study was to show the differences in the content of antioxidant compounds between hot- and cold-prepared mate beverages. The antioxidant capacity of the infusions was tested using the Folin-Ciocalteu, ABTS, and DPPH assays. A comprehensive analysis of different phenolic and other constituents was performed with the use of high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). The hot-prepared infusions on average contain considerably more active compounds than the cold-prepared infusions, which resulted in greater antioxidant activity of hot-prepared beverages. While the hot-prepared infusions of pure yerba mate contained a similar amount of bioactive compounds as those with different additives, for cold-prepared beverages, greater antioxidant activity was found for samples containing additives. In both conditions, the lowest antioxidant activity was noted for <i>Ilex guayusa</i>, which contained less rutin, caffeoylquinic acids, dicaffeoylquinic acids, and theobromine, but more caffeine.