Rheological investigation of the interaction between amylose and κ-carrageenan

By combining rheological and turbidity measurements, the interaction and viscoelastic properties of amylose–κ-carrageenan mixtures were investigated under conditions allowing gelation of the former and gelation or non-gelation of the latter. Amylose concentration was kept constant (1.34 wt%) and carrageenan content was varied from 0.093 to 1.38 wt%. Amylose was dispersed in water at 150°C and its gelation was induced by quenching aqueous solutions from 80 to 25°C. When desired, carrageenan gelation was also induced by addition of 20 mM KCl. Absorbance and gel-cure profiles were highly dependent on carrageenan concentration and presence of salt. The storage modulus at 15 h depended strongly on carrageenan concentration; for concentrations