LAUSR

Abstract Rheological and dielectric behavior of milk/sodium carboxymethylcellulose (Na-CMC) mixtures with 0–10 g/L Na-CMC were investigated from 15 °C to 55 °C. Shear viscosity and viscoelastic behavior of milk/Na-CMC mixtures are mainly controlled by Na-CMC. Raising temperature has an obviously influence on viscoelastic behavior of mixtures. Meaning, the interchain hydrogen bond interaction among Na-CMC chains and the hydrogen bond interaction between Na-CMC chains and water molecules change with temperature. At 55 °C, the viscoelastic behavior of mixture with 2.5 g/L Na-CMC is different from that of the others. That indicates temperature has a larger impact on chain conformation of Na-CMC at the mixtures containing lower Na-CMC concentration. The dielectric spectra show one relaxation caused by loosely bound counterions. With increasing temperature and Na-CMC concentration, the changes of relaxation time τ and dielectric increment ∆e are critically relevant to the numbers of bound counterions and chain conformation of Na-CMC. The contribution of Na-CMC to the dc conductivity of mixtures notably changes at 45 °C. It reveals the free ion numbers and viscosity of bulk phase obviously changes at 45 °C. The results reveal the stability of mixtures reduce with increasing temperature.