Rheological properties of food
The rheological properties of food materials are important in determining both texture and behaviour when subjected to physical forces and forced to flow. Here are four examples of how we can study the rheological properties of raw materials, intermediate products such as batters and doughs, and final products.
Oscillation: a small deformation is applied and the response measured, while maintaining the integrity of the test material. This provides insight into the structural properties of the material and the likely stability over time.
Viscosity: Rapid Visco Analysis measures the viscosity build up of starch–based materials as they are heated. The rate of heating and degree of shear force on the viscosity of the material can be measured as can the effect of salt, emulsifiers, enzymes and other materials.
Drop shape analysis: surface or interfacial properties play an important role in foam and emulsion creation and stability. The wetting behaviour of a liquid when in contact with a solid surface can be determined by making contact angle measurements.
Flow measurements: the distance a sample flows in a given time indicates the consistency of products such as sauces, purees, salad dressings, and batters.