Slow-cooling (1.25 K min(-1)) crystallization experiments were conducted on bulk and emulsified samples of trilaurin, tripalmitin and tristearin. In addition, isothermal crystallization experiments were performed on bulk and emulsified trilaurin. Emulsified samples show greater supercooling, and lower crystallization rates compared to bulk samples. The temperature dependence of the crystallization rates was analyzed. Slow-cooling crystallization experiments on milkfat samples do not show the same clear differences between bulk and emulsion samples. The temperature dependences of the crystallization rates for bulk and emulsion samples were very similar. The results, particularly the comparisons between bulk and emulsion samples, and the comparisons between triglyceride and milkfat, suggest that in emulsified triglyceride samples the rate-determining step is nucleation. Both nucleation and propagation contribute to the crystallization rate for bulk triglycerides. For milkfat samples, the results suggest that there may be an unusually high concentration of active nuclei influencing bulk crystallization rates of the tow-melting fraction.