Determination of Hydrogen Peroxide in Foods Containing Catalase Activity

Abstract

In the determination of hydrogen peroxide in foods containing catalase by the oxygen electrode method, a part of the hydrogen peroxide is decomposed enzymatically. Therefore, the sample was treated with metaphosphoric acid to inactivate catalase and hydrogen peroxide was determined by the oxygen electrode method. With this metaphosphoric acid method, more than 70% of spiked hydrogen peroxide was recovered from chicken liver at the 50μg/g level, from semi-dried sardine at the 5μg/g level and from shirasuboshi at the 1μg/g level.Hydrogen peroxide contents in the various foods were determined and compared by the oxygen electrode method with and without metaphosphoric acid pretreatment (original method and metaphosphoric acid method). Hydrogen peroxide in food containing low catalase activity (not more than 4U/g) gave almost the same value in both methods. Hydrogen peroxide in food containing high catalase activity (more than 20U/g) could not be detected by the original method, but could be detected by the metaphosphoric acid method.It is recommended that hydrogen peroxide in food containing high catalase activity should be determined by using the metaphosphoric acid method.