Steady and dynamic oscillatory shear rheological properties of ketchup-processed cheese mixtures Effect of temperature and concentration

The steady and dynamic shear properties of ketchup-proce.,sed cheese (K-PC) mixtures were investigated at different temperatures (10-50 degrees C) and PC concentrations (0-30%) The K-PC mixtures showed a shear thinning behavior with low magnitudes of yield stress, The consistency coefficient (K) and apparent viscosity (eta(50)) decreased with increase in temperature and concentration The mixtures followed the Arrhenius temperature relationship indicating that the magnitudes of activation energies (E-a) were in the range of 8 83-17 16 kJ mol(-1) Storage (G') loss (G '') and complex (G*) modulus increased with increase in frequency while complex viscosity (eta*) decreased The K-PC mixtures at concentrations of 0-15% exhibited weak gel-like behavior Increase in the PC concentration resulted in a decrease in G '' G' G '' and eta* up to the 15% of PC concentration showing a plateau value between 0% and 30% concentrations Cox-Merz rule was not applicable to K-PC mixtures (C) 2010 Elsevier Ltd All rights reserved