Most of available literature on gellan gum reports methods of fluid gel preparation either at quiescent cooling conditions or under controlled shear in rheometers (in situ preparations) . Conversely, little information is available on gellan fluid gel preparation conducted with homogenisers. The latter approach is quite interesting to fill the gap between fundamental research and industrial applications of gellan fluid gels. The overall objective of this research was to explore the chances to obtain tailor-made gellan fluid gels with tuned rheological properties, concerning their applications as dispersion stabilisers. Different mechanical protocols were used to disturb the quiescent gel setting as temperature decreased once hydration and addition of gel-promoting ions were completed. A further interesting point considered was the batch reproducibility and the effect of the nature and concentration of gel-promoting ions. Gellan fluid gels can be considered as suspensions of microgel particles, whose average size is controlled by the shear stresses applied during gelation. Therefore, serrated or star parallel plate geometries were used to prevent wall-depletion phenomena when conducting rheological measurements out of the linear viscoelastic range. A wide range of rheological techniques were used to gain a deeper insight into the shear flow of gellan fluid gels, involving small amplitude oscillatory shear (SAOS), creep within and out of the linear viscoelastic range (LVR), multi-step flow curves, start-up at the inception of shear and flow interrupted experiments as well as nonlinear creep/recovery/nonlinear creep series to check the structure recovery after shear.
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