Determination of hydrogen peroxide in beverages by high-performance liquid chromatography with fluorescence detection

A high-performance liquid chromatographic method is described for the determination of hydrogen peroxide in beverages. The method involves the enzymatic conversion of hydrogen peroxide into formaldehyde by catalase-methanol, followed by the derivatization of formaldehyde with 4-amino-3-penten-2-one. The reaction was carried out under the flow of nitrogen, which allows the detection of hydrogen peroxide without interference from reducing substances such as ascorbic acid. More than 90% of hydrogen peroxide spiked at the 2 ppm level was recovered from several beverages. The method exhibits good linearity, accuracy and precision, and the minimum detectable level was 0.05 ppm.