Characterization of rheological properties of systems containing sugar substitutes and carrageenan

The effects of addition of kappa-carrageenan to solutions containing 40% (w /w) sugar substitute on the rheological properties of these systems were in vestigated at 25 degrees C using a rotational viscometer at rotational spee ds of 6, 12, 30, and 60 rev min(-1). The flow behaviour of the solutions wa s adequately described by the power law model with or without yield stress. The consistency index (K) and the flow behaviour index (n) were determined from shear stress vs. shear rate data. The flow parameters of the solution s depended on the carrageenan concentration. The apparent viscosities of th e systems decreased with increasing shear rate, indicating pseudoplastic be haviour. The final carrageenan concentration was found to be an effective f actor controlling the degree of sliminess of the model food systems studied .