6533b828fe1ef96bd1288d5a

RESEARCH PRODUCT

Effect of several electrolytes on the rheopectic behaviour of concentrated soy lecithin dispersions

J. FiguerueloMaria ManconiF. MolinaD. SeylerA.o. VilaJ. Aparicio

subject

Shear ratechemistry.chemical_compoundColloid and Surface ChemistryAqueous solutionChromatographyChemical engineeringChemistryPhosphatidylcholineSonicationVesicleShear stressZeta potentialElectrolyte

description

Abstract Concentrated dispersions of soy lecithin (60 g/L) prepared by sonication-freezing–unfreezing method show a non-newtonian behaviour and a significant rheopexy. Shear stress versus shear rate plots shows a loop hysteresis area, which have been studied in soy lecithin dispersions prepared with aqueous solutions of various electrolytes (NaCl, CaCl2, MgCl2 and AlCl3) with concentrations in the range 10−5 to 10−2 mol/L. Also we have studied the effect of different pH on soy lecithin dispersions. The results have revealed a very sensitive influence of nature, valence and concentration of the respective cations and the pH value on the loop hysteresis area values. It seems to indicate that the vesicle formation by segregation process followed by vesicle fusions is involved in the rheopectic effect.

https://doi.org/10.1016/j.colsurfa.2005.05.050