Abstract: The present study was carried out to evaluate the effects of micelle casein concentrate (MCC), calcium caseinate (CaC) and processing conditions (sterilization and two homogenization cycles) on the stability of recombined dairy cream as assessed by measurement of particle size, interfacial protein concentration, viscosity and microrheological properties. The results showed that the instability indexes of MCC cream with MCC concentration of 1.0% and 2.0% (m/m) were 0.396 ± 0.011 and 0.032 ± 0.001, respectively, suggesting a better stability at higher MCC concentration. However, an opposite trend was observed for CaC cream. An significant increase was observed in the D3,2 (P < 0.05), adsorbed protein amount and viscosity of MCC cream after being subjected to sterilization, and the mean square displacement (MSD) value decreased significantly. However, no apparent change was observed in the D3,2, viscosity or MSD of CaC cream (except for the MSD of 2.0% CaC cream), while the adsorbed protein amount increased from 3.9–5.5 to 5.2–7.0 mg/m2. After the second homogenization, the D3,2, adsorbed protein amount and viscosity of MCC cream decreased significantly (P < 0.05), whereas an increasing trend was observed in MSD values. The D3,2 of 1.0% CaC cream decreased from (2.80 ± 0.10) to (2.06 ± 0.11) μm, whereas no significant change occurred in other physicochemical parameters. The 2.0% MCC cream exhibited the best stability among all the recombined cream despite the fact that MCC showed poorer emulsifying capacity in comparison with CaC. Furthermore, the balance among the physicochemical characteristics of recombined dairy cream and consequently its stability changed to some extent after sterilization and secondary homogenization (in particular for MCC cream).

Key words: micelle casein, calcium caseinate, recombine dairy cream, process, stability