ungelled

Ungelled is an adjective describing a substance that has not formed a gel under specified conditions, or a system in which gelation has not yet occurred. The term is used across disciplines such as chemistry, polymer science, and food science to distinguish a sol or liquid state from a gel state, and to track gelation over time.

In experimental contexts, a sample may be described as ungelled at a given time point if a continuous three-dimensional network has not yet developed. Rheological measurements often accompany this description; ungelled systems tend to show predominantly viscous behavior with a relatively low storage modulus, whereas gelled systems exhibit a rising elastic response as the network forms.

Gelation depends on factors including the concentration and nature of gelling agents, temperature, pH, ionic strength, and processing time. Insufficient cross-linking, inappropriate ions, or conditions that prevent network formation result in an ungelled state, while reaching the gel point yields a solid-like, self-supporting gel.

Although the term is primarily descriptive in laboratory settings, ungelled serves as a useful contrast to gelled or set states in studies of hydrocolloids, polymers, and composite materials.

See also: gelation, gel point, rheology, hydrocolloid, cross-linking.