Abstract THERE is current interest in using egg white (EW) enzymes to test the efficiency of EW pasteurization (Henderson and Robinson, 1969; and Donovan et al., 1970). Catalase or the catalase like activity of EW has been considered for such use. Earlier workers (Loew, 1901; Winternitz and Rogers, 1910; Pennington and Robertson, 1912; Lineweaver et al., 1948; and Lloyd and Harriman, 1957) assumed that catalase was a component of EW. Baker and Manwell (1962) have raised doubt about its being present in EW. They observed results indicating catalase activity after separating EW proteins by starch gel electrophoresis. The activity, however, was located on regions of electrophoretograms commonly associated with the EW proteins ovalbumin and conalbumin. They did not expect a protein the size of catalase to migrate with ovalbumin. In addition, a qualitative test for iron indicated that iron was present in those portions of the gel and it was assumed…