Generation of Hydrogen Peroxide in Beer and Selected Strong Alcoholic Beverages

Abstract

The generation of hydrogen peroxide has been documented in various plant-based beverages, such as coffee, tea, herbal infusions and wine, as well in energy drinks containing ascorbate and in plant-based food. There are no data in the literature on the presence and generation of hydrogen peroxide in beer and strong alcoholic beverages containing plant material. This study aimed to examine whether beer and selected strong alcoholic beverages (brandy, whisky and fruit liqueurs) contain hydrogen peroxide. The presence of hydrogen peroxide was found in freshly opened brandy, whisky, liqueurs and most diluted beers; subsequent incubation in an air atmosphere led to the generation of hydrogen peroxide. The presence of the electron paramagnetic resonance (EPR) signal of the semiquinone radical and the generation of the superoxide radical demonstrated in selected alcoholic beverages by the superoxide dismutase-inhibitable reduction of Nitrotetrazolium Blue and oxidation of dihydroethidium are in agreement with the two-step mechanism of generation of hydrogen peroxide by the autoxidation of phenolics. These results broaden the list of beverages containing and producing hydrogen peroxide.