Die rheologische Charakterisierung der Stärkegele

Rheological characterization of starch gels is a complicated problem as the measured values represent only an apparent viscosity. They depend on shearing stress respectively shearing rate and thus also on the type of viscosimeter used. Moreover starch gels are thixotropic, which brings about additional difficulties in measuring procedures and reproducibility of measured values. This paper has pointed out the possibilities of rheological characterization of starch gels by the parameters of rheological equations, as well as by the coefficients of thixotropy. Following the values of these parameters and coefficients it is possible to examine the changes in starch gels, caused by different factors (concentration changes, ageing, chemical modifications etc.).