Phase separation in optically opaque emulsions

Creaming of the dispersed oil phase in opaque oil-in-water emulsions was followed as a function of time and position using proton magnetic resonance. Measurements of T₁ along a vertical slice were used to quantify the oil-phase concentration. Emulsions were also described by laser-diffraction particle-size analysis to compare particle-size analysis with creaming behavior as determined by T₁ measurements in model triolein-in-water emulsions and more complex milk fat-in-water emulsions. Particle-size distributions failed to accurately predict the measured creaming behavior in the emulsions studied. Measurements of component nuclear relaxation were shown to be useful for characterizing oil-phase migration as a function of surfactant level, dispersed phase volume, and crystallization behavior of the lipid phase in emulsions.