Design of natural origin foundations based on rheological studies to select raw materials, to optimize textures and to predict the stability

To find equally performing natural origin alternatives to synthetic raw materials, we developed a new foundation in an oil in water (O/W) emulsion type, starting from an existing formula and increasing the respective Natural Origin Index (NOI) trying to obtain equivalent cosmetic performances in structure and texture terms. The systematic use of rheology as the main characterization tool enabled the development of predictive structure/performance relationships. Dealing with viscoelastic systems, it was possible to investigate samples with continuous and oscillatory rheology. The study led to two different natural origin foundations (NOI higher than 81%), containing respectively two different gelling systems. Thanks to rheology were possible to determine the suitable natural raw materials replacing the non-natural ones, pointing to unstable formulas during the early stages of the study and finding a correlation with what happened in rheometry shortly after the formulation and after months in thermal stability, optimizing the formulation. In the end, rheometry and Texture Analysis allowed us to conduct an in-depth study of the texture also pointing to one of the two natural origin foundations obtained as the most similar to the standard foundation in cosmetic characteristics.