Effect of sodium caseinate on the stability of cream liqueurs

Abstract

The apparent viscosity of cream liqueurs prepared with different commercial sodium caseinates increased on storage at 45°C at rates and to extents that were dependent on which caseinate was used in the cream liqueur preparation. Increases in the apparent viscosity of fat free and fat free, micellar casein and whey protein free liqueurs indicated that differences in the caseinate s per se, rather than differences in interfacial absorption of the caseinates or the inclusion of micellar casein and whey proteins with the cream serum, caused the differences in increases in the apparent viscosity of cream liqueurs on storage at 45°C. No significant correlation was found between the calcium content of the caseinates and increases in the apparent viscosity of the liqueur systems on storage at 45°C. Addition of 2‐mercaptoethanol to liqueurs after manufacture caused large increases in apparent viscosity, indicating that sulphydryl interactions may be important. Addition of NaCl to cream liqueurs resulted in an immediate increase in apparent viscosity, and on storage at 45°C for seven days, the liqueurs gelled, developed a high apparent viscosity or underwent phase separation, depending on which caseinate was used in the manufacture of the cream liqueur. Thus changes in the apparent viscosity of cream liqueurs on storage at 45°C are caseinate dependent and the results presented suggest that electrostatic and sulphydryl interactions may be involved in these changes.