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The flow behavior and dynamic viscoelasticity of deacetylated gellan gumsolutions were measured with a rheogoniometer. The gellan gum showed Newtonian behavior with a range of concentration below 0.9%, but plastic flow behavior above 1.0% at 25°C. A gelation occurred in polysaccharide concentrations over 0.8 % upon cooling, and a melting temperature was observed at 15 and 20°C at 0.8 and 1.0 % concentrations, respectively. In the presence of CaCl2 (6.8mM), the dynamic modulus of gellan gumshowed a very high value at low temperature at the concentration of 0.2%, and increased with increasing temperature up to 80 C, which was estimated to be a melting temperature, then it decreased. However^thegellan showeda little increase of dynamicmoduluseven at the concentration of0.4 %in the presence ofNaCl (16.6mM) or KC1 (13.5 mM). Gelation occurred for gellan gum in acid and alkaline range after reaching a pH 2.6 and ll.2 by addition of 100mMHC1and Ca(OH)2. The rheological characteristics of the gellan gummolecules might be essentially attributed to intra-and inter-molecular associations, possible structures of which have been proposed.

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