Abstract: | Measurements have been made of the shear modulus for calcium, potassium and sodium ι-carrageenate gels as a function of biopolymer concentration and temperature. The results are discussed in terms of the application of rubber elasticity theory. Calcium ι-carrageenate gels appear to possess a random glass-like structure whereas both sodium and potassium ι-carrageenate gels form a pseudocrystalline structure. These differences are tentatively attributed to differences in the solubility of the salt forms which, through controlling the gelation temperature, moderate the kinetics of the gelation process. |