Rheology of sheared gels based on low acyl-gellan gum

Sheared gels containing 0.2 wt% low-acyl gellan gum were prepared by different processing protocols using Na(+) or Ca(2+) as gel-promoting ions. Rheology and confocal laser scanning microscopy were used to gain information on the sample structure. Confocal laser scanning microscopy revealed the formation of a heterogeneous microstructure consisting of a dispersion of gel-like clusters. Small amplitude oscillatory shear stress results indicated that their viscoelastic properties had a predominant elastic component. Flow curves exhibited very high viscosities at low shear stress, an apparent yield stress and very shear thinning behaviour, supporting their applications as a stabilizer.