The control of oil-in-water emulsion consistency using mixed emulsifiers

Mixtures of emulsifiers of the surfactant-fatty alcohol type are widely used to stabilize oil-in-water emulsions and to alter their consistency from fluid to semi-solid. A mechanism, involving the formation of a viscoelastic network in the continuous phase, is proposed to explain this self-bodying action. Evidence has been adduced from published data on a variety of systems. Support for this concept is also provided by the results obtained from a concentric cylinder study of the rheology of liquid paraffin in water emulsions containing a fixed concentration of cetostearyl alcohol and varying amounts of polyoxyethylene sorbitan monooleate, cetomacrogol 1000, sodium dodecyl sulphate or cetrimide.