Viscoelasticity, low shear flow, microstructure, and physical stability of a commercial suspoemulsion pesticide are studied to serve as a point of reference for the development of new suspoemulsions. Creep compliance tests allow the zeroshear rate viscosity, g 0 , to be calculated. As expected, the values of g 0 decrease with temperature. The storage modulus is higher than the loss modulus until a crossover frequency, x*, which is located at the lower frequencies studied. The dynamic parameters decrease with higher temperature and x* increases in agreement with a faster relaxation mechanism. Multiple light scattering predicts the occurrence of a creaming destabilization process, whose kinetics depends on temperature. Rheological measurements are demonstrated to be a powerful tool to assist in the prediction of destabilization processes together with the multiple light scattering technique.

Low-acyl gellan gum fluid gels were obtained using two different gel-promoting cations under the same processing conditions and their rheological properties were investigated.For that reason, stress and frequency sweeps measurements and flow curves tests were carried out. Small amplitude oscillatory shear assays demonstrated that these materials exhibit weak gel behaviour despite the shape of their mechanical spectra being similar to those obtained from strong gels. However, the existence of a weak gel structure was confirmed by the fact that the difference between the elastic and viscous components was of only one order of magnitude. In addition, a reduction in the storage and lost modules and the viscosity as a function of the applied shear was observed with increasing cation concentration. Finally, in order to produce fluid gels, a higher concentration of the monovalent cation was required than when divalent cations were employed in the lowacyl gellan gum fluid gels formulation.

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