Using NMR and laser diffraction, it could be seen that median and width of O/W/O emulsion DSD reduce upon processing in the colloid mill. This size reduction might be due to both loss of inner oil phase or processing conditions. A size reduction due to processing conditions might have implications for the rheological determination of EE. At constant dispersed phase, the viscosity of an emulsion increases with decreasing droplet size due to higher internal friction. EE might therefore be overestimated. In order to evaluate the impact of droplet size reduction on emulsion viscosity, W/O emulsions were processed in the colloid mill for 3 min and their relative viscosity was compared to stirred W/O emulsions (Fig. 6). It can be seen that there is only a minor impact on relative viscosity.