FAQs

What explains the unique thixotropic (shear-thinning with time-dependent recovery) behavior of iota-carrageenan gels?

The fluid rheology of iota-carrageenan is highly thixotropic due to its mild, reversible calcium-bridged network. When the structured iota gel is subjected to mechanical shear (such as pumping or agitation), the weak electrostatic calcium bridges between the adjacent double helices are disrupted, causing the gel structure to break down and the apparent viscosity to drop instantly. Crucially, because the iota polymer chains carry strong negative charges that repel each other, they remain perfectly ordered and aligned without irreversibly clumping. Once the shear stress is removed, the ionic bridges spontaneously reform, allowing the gel structure to fully recover over time without altering its original texture.