Bile salt lipid emulsions were prepared which simulated the emulsified oil-micellar phase system of the small intestinal content during fat digestion.Application of such emulsions to gel columns prepared and eluted with 6 mM sodium taurodeoxycholate separated an emulsion phase and a micellar phase. The distribution of lipid solutes into the two phases under these conditions was measured.Micellar dimensions were larger as lipid concentrations were increased. Inclusion of multiple lipid classes resulted in larger micellar particles.Monoglyceride and fatty acids were eluted completely in the micellar phase under these conditions. Minimal measurable amounts of triolein were recovered in micellar solution. This was confirmed by extraction, chromatographic separation and quantitative analysis. As diolein concentration was increased, less was recovered in the micellar phase. When monoglyceride was added, more diolein entered the micellar phase. Addition of triglyceride enhanced the distribution of diolein into the emulsion phase.