CHARACTERISTICS OF HEAT-INDUCED NETWORKS FOR MIXTURES OF OVALBUMIN AND LYSOZYME

Proteins with opposite charges were heated together to assess the impa ct of this combination on the characteristics of the heat-induced prot ein networks produced. The thermal properties and dynamic theological characteristics of heat-induced networks were evaluated for ovalbumin, lysozyme, and mixtures of the two at ratios ranging from that natural ly found in egg white to 1:1. Ovalbumin formed stronger (high G' and G ''), more well cross-linked networks (lower tan delta value) than lyso zyme. Network formation was unaffected by mixing ovalbumin and lysozym e at pH 5.5, whereas at pH 7.0 and 8.5 network strength increased and cross-linking in the network decreased as the relative proportion of l ysozyme was increased. Mixed protein systems can produce stronger, les s structured networks than pure proteins. Removal of lysozyme from egg albumen can adversely affect its gel strength and hence reduce its co ntribution to the textural properties of food products.