What You Need to Know
Alginate polymers (β‑D‑mannuronic and α‑L‑guluronic acids) bind divalent Ca²⁺ ions in an "egg‑box" arrangement, creating a three‑dimensional network. Gel strength depends on alginate concentration (0.5–1.5 % w/v), calcium ion concentration (≥0.1 M), pH (4.5–6.5) and temperature (20–25 °C). Excess heat (>60 °C) hydrolyzes the polysaccharide backbone, weakening or preventing gelation.
The Science
Primary Reaction
Calcium‑induced cross‑linking of alginate chains forming calcium alginate gel