A new method for the continuous determination of H2O2 is described based on the catalytic decomposition of H2O2 by LaCoO3. Oxygen liberated is measured by a gas meauuring burette. γ-irradiated catalyst enhances the catalytic activity and decreases the time required for complete decomposition. The procedure is suitable for microdetermination of H2O2 in various food products. © 1986 Akadémiai Kiadó.