Studies on ovalbumin-s-ovalbumin transformation. Part IV. Changes in the heat-induced gelling properties of ovalbumin during its conversion to s-ovalbumin.

Both ovalbumin and s-ovalbumin gave maximumgel strength at both sides of the isoelectric point. Maximumgel forming pHs of s-ovalbumin were almost the same as those of ovalbumin, but maximumgel strength values of s-ovalbumin were much smaller than those of ovalbumin. Although the gel strength of both proteins increased with increased heating temperature, the gel strength of s-ovalbumin was much smaller than that of ovalbumin at every heating temperature. About the results of creep experiments, all heat-induced gels were analyzed as a four-element model and the magnitude of all the parameters of both s-ovalbumin and intermediate was smaller than that of ovalbumin. Scanning electron microscopic studies showedthat the structure of ovalbumin gels was very fine comparing those of s-ovalbumin and the intermediate.