3.2. Phenolic compounds
The concentration of individual phenolic compounds, total phenolic
acids, total flavonoids, total phenolic compounds
determined by HPLC as the sum of individuals (TPC by HPLC)
and total phenolic compounds determined by Folin–Ciocalteu
method (TPC by F-C) is presented in Tables 2 and 3.
In untreated beverages, the concentration of TPC by HPLC
was in the range of 25.4 to 34.4 mg/100 mL, and between 76
and 125 mg of gallic acid equivalents/100 mL by F-C method.
Flavonoids were the predominant phenolic compounds of all
the analysed beverages, while sinapic acid and (+)-catechin were
not detected.