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.Maximum gel 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.Heat-induced gelling properties are one of the most important functional properties of food proteins.Although gelling properties differ greatly amongmany kinds of proteins, few studies have been madeon the relationship between the structure and gelling properties of proteins.Recently, HeggX) compared gelling