Rheology Solutions has measured the effects of gels upon mouth-feel. The use of gels in the food and pharmaceutical industry to alter products, control their consistency, and contribute to the structure and appearance of the product is enormous.
By altering gels one can, for example produce a soft and chewy candy as opposed to a hard candy. These issues are also important in the pharmaceutical industry, since oral drugs will have a particular mouth-feel associated with their digestion. Children prefer a gummy consistency, whereas adults generally prefer a liquid feel.
The question arises, how can the rheological (flow) properties of gels be characterized? It is generally not sufficient to measure flow curves, since the flow curves yield no information about the elastic properties of the gel. A better technique is forced-oscillation, which directly measures the magnitude of the elastic and viscous components.