What You Need to Know
Agar forms a rigid, heat‑stable network through extensive hydrogen bonding between agarose chains, while carrageenan forms a flexible, ion‑dependent network via helical aggregation of sulfated galactan chains in the presence of K⁺ or Ca²⁺ ions. The gelation is thermoreversible, melting at higher temperatures and setting upon cooling.
The Science
Primary Reaction
Thermoreversible polymer network formation via hydrogen bonding (agar) and ion‑mediated helix formation (carrageenan).