ABSTRACT
Oregano essential oil emulsions (W/O) were prepared using different emulsifiers’ blend concentrations of Tween 80/Span 20, to study their phase separation during storage and to optimize the homogenization processing parameters by minimizing the droplet size of emulsions. Phase separation followed a second-order kinetic model, and relationships between the kinetic parameters and the blend concentrations of emulsifiers were established for determining the best emulsion formulations. The instability mechanism of emulsions demonstrated to be Ostwald ripening; therefore, by means of surface response methodology, mechanical homogenization parameters (11,700 rpm for 12 minutes at 1°C) were specified in order to minimize the droplet size of emulsions (1.02 ± 0.12 µm).
GRAPHICAL ABSTRACT
Acknowledgments
Authors acknowledge the National Council for Science and Technology (CONACyT) of Mexico (project CB-2011, SEP-CONACyT, number 168709) and Universidad de las Americas Puebla (UDLAP) for the grant received for this research. Author Cardoso-Ugarte gratefully acknowledges CONACyT and UDLAP as well for the financial support for his PhD studies.