Measurement of gel characteristics

In the case of solutions formed from non-gelling hydrocolloids determination of viscosity and viscoelastic properties using rotational rheometers can provide an almost complete description of the rheological properties of interest. Additional information which is sometimes required are extensional viscosities which are very difficult to measure and changes from a particulate system to a “solution” for example starch gelatinisation or dissolution of hydrocolloids. For gels the situation is different. Gel texture is multidimensional. Rotational rheology provides important information but other techniques are required to provide the full picture. This paper covers some of these additional methods. Topics that will be considered are:-

• • Difference Between Fundamental and Empirical Rheological Methods

• • Industrially Important Properties of Gels

• • Empirical Methods

• • Fundamental Methods