STABILIZING OIL-IN-WATER EMULSIONS WITH YAM BEAN (PACHYRHIZUS EROSUS L. URBAN) SOLIDS

 

Y. Carrera, E. García-Márquez, E. Aguirre-Mandujano, M.E. Rodríguez-Huezo, and J. Alvarez-Ramirez

 

 

Yam bean (Pachyrhizus erosus L. Urban) solids (YS) were used at concentrations of 3, 5 and 7 % w/w for stabilizing oil-in-water emulsions with a 0.15 mass fraction (E3, E5 and E7). Higher YS concentrations produced emulsions with smaller average particle size distribution, more marked shear thinning behaviour, and higher solid-like (tan δ < 1) viscoelastic properties. Optical micrographs revealed that the rheological properties, particle size distribution, and stability of the emulsions were predominantly associated to the formation of 3-D particles network in the continuous phase that immobilized the emulsion droplets. The micrographs also showed small sized YS fragments adsorbed at the oil–water interface, contributing with a steric stabilization term to emulsions stability. Variations in the rheological properties of the emulsions with aging time (14 days) were less pronounced when using higher YS concentrations.