Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
2434505 | International Dairy Journal | 2013 | 7 Pages |
The viscosity and the frequency dependent shear moduli of dense calcium caseinate (CaCN) and sodium caseinate (NaCN) suspensions were investigated as a function of concentration (50–300 g L−1) and temperature (10–50 °C) at pH 6.7. Both systems form visco-elastic suspensions with a viscosity that increases strongly with increasing concentration and decreasing temperature. An important effect of the counter-ion on the visco-elastic properties was observed that is attributed to the specific binding of calcium, which reduces the electrostatic repulsion and induces a net attractive interaction between caseins. The latter may lead to micro-phase separation as was observed by confocal laser scanning microscopy. Mixtures of NaCN and CaCN were significantly different from pure NaCN if they contained more than 50% CaCN. The equivalence between NaCN with added CaCl2 and CaCN is discussed.