AbstractPreparations of purified ovomucin complex have been obtained from samples of thick egg white which were liquefied during incubation at 37 °C under sterile conditions. Chemical analyses of the ovomucin complex and analytical ultra‐centrifugation of fully reduced derivatives of the ovomucin complex obtained from thick egg white thinned by incubation at 37 °C have shown that these preparations, unlike those obtained from “fresh” thick egg white, contained only small quantities of β‐ovomucin. It is postulated that β‐ovomucin is converted to a more soluble form during the natural thinning of thick egg w