Table shows the results of the flow shear rate sweep tests. In regions that were both low pH and low mole ratio of CAPB / SLSar turbid systems were observed. These liquids were white and cloudy and, under cross polarised microscopy, showed an absence of crystalline material. Shortly after blending these liquids had extremely high zero shear viscosities of tens of thousands of mPa s. After a few hours these liquids transitioned to low viscosity. It is likely that this behaviour is related to the protonation and precipitation of the acid form of SLSar at a pH close to or below its pK a of 4.5. Similar effects were encountered by Vu et al. and we agree with their assessment that these systems are best discarded due to their unsuitability for formulation. The remaining systems listed in Table were clear and colourless liquids with differing viscosity as reported.