Formulations of selected Energy beverages promote pro-oxidant effects of ascorbic acid and long-term stability of hydrogen peroxide

Recently, autoxidation mediated by ascorbic acid (AA) and other ingredients, has been implicated in generation of hydrogen peroxide (H2O2) in so-called Energy beverages. Here, we report the use of cyclic voltammetry and the FOX assay to monitor at short and long incubation times, respectively, the production and stability of H2O2 generated by AA and redox-active ingredients. Levels of H2O2 in Energy drinks (36.5 +/- 4.0 mu M at 4 C and 64.2 +/- 7.6 mu M at 20 degrees C) were found to be stable or increased (p < 0.05) upon vessel opening. A predictive model for the production of H2O2 as a function of AA concentration, temperature and incubation time, and depending on ingredients present, indicated that H2O2 peaked at 91-726 mu M after 1 day and declined to 42-60 mu M (4 degrees C) or zero after-10 days. The research supports that levels of H2O2 in beverages containing anti-oxidant mixtures and dissolved oxygen should be monitored and formulations modified to avoid AA autoxidation.

Automated summary

Recently, it has been discovered that autoxidation mediated by ascorbic acid (AA) and other ingredients in energy beverages can generate hydrogen peroxide (H2O2). In this study, cyclic voltammetry and the FOX assay were used to monitor the production and stability of H2O2 generated by AA and redox-active ingredients at short and long incubation times, respectively. The levels of H2O2 in energy drinks were found to be stable or increased upon vessel opening. A predictive model showed that H2O2 peaked after 1 day and declined over time. This research highlights the importance of monitoring H2O2 levels and modifying formulations to avoid AA autoxidation in beverages.