Strategy for the development and characterization of environmental friendly emulsions by microfluidization technique.

Abstract

This study reports on the procedure for the development of ecological emulsions formulated with renewable components as a sustainable alternative to products containing traditional organic solvents. Firstly, in order to evaluate the interfacial and emulsifying properties of a green surfactant (Levenol F- 200), the adsorption isotherm and interfacial rheology at a biosolvent/water interface were investigated. In the second step, Levenol F-200 and the renewable biosolvent (a-pinene) were used in order to obtain stable concentrated emulsions by microfluidization technique. The influence of different configurations in the Microfluidizer, namely Y and Y þ Z, on the stability and rheological properties of these emulsions was studied. The characterization of these green systems involved droplet size distributions, Cryo-SEM and optical microscopy, flow and oscillatory shear tests, as well as multiple light scattering. Emulsions with series configuration showed smaller droplet size and better stability against creaming. Lastly, a fumed silica (Aerosil 200) was used as a thickener to modify the rheological properties of the emulsions and hence, to improve their physical stability. Furthermore, this work provides relevant new findings and a systematic strategy for the development of stable green emulsions using an ecological formulation and series configuration in the microfluidization technique.