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The exothermic and endothermic peaks in cooling and heating curves of differential scanning calorimetry (DSC) for gellan gum gels without and with potassium chloride and sodium chloride were analyzed. The gelling and melting temperatures shifted to higher temperatures with increasing gellan and salt concentration in the concentration range of gellan from 0.3 to 2.0% (w/w). The exothermic and endothermic enthalpy increased with increasing gellan and salt concentrations. Cooling DSC curves showed one exothermic peak for samples with salts and at low gellan concentration. Heating DSC curves showed many peaks for all samples except 0.3% (w/w) gellan gum gels. The sol-gel transition of samples was examined numerically by using a zipper model approach. The introduction of cations increases the number of junction zones or zippers and decreases the rotational freedom of parallel links. This makes the structure of junction zones more heat resistant, and increases the elastic modulus of the gel.

The rheological properties of carrageenanlgelatin and agarlgelatin mixed gels were investigated by measuring the rupture properties, the texture parameters and the dynamic viscoelasticities. f i e melting point, transparency and syneresis of these gels were measured in order to obtain the relationship with the rheologicalproperties. The physical properties of the two mixed gels were slightly dgferent. The agarlgelatin mixed gels generally showed the hindered effect of gelatin. f i e brittleness of agar gel disappeared on mixing with gelatin. It then became aflexible, cohesive and transparent gel. Carrageenanlgelatin mixed gels showed a decrease in the values of almost all of the mechanical properties when compared with carrageenan gels. However, the rupture properties of the C0.5 mixed gel were much higher than those of simple carrageenan gels.

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