What You Need to Know
Pectin molecules (polygalacturonic acid chains) cross‑link either via calcium‑mediated ionic bridges (egg‑box model) in low‑methoxyl pectin or through acid‑induced hydrogen bonding in high‑methoxyl pectin. The gel strength is governed by pH, calcium or sugar concentration, temperature, and the degree of methoxylation, which together dictate the extent of chain association and water immobilization.
Steps
- 1.
Confiture de fraises (French): Creates the characteristic glossy, spreadable texture of traditional strawberry jam
- 2.
Marmalade (British): Allows suspension of citrus peel in clear gel matrix
- 3.
Gelled fruit spheres (Modernist cuisine): Enables spherification through controlled calcium diffusion
The Science
Primary Reaction
Ionic cross‑linking (Ca²⁺) and hydrogen‑bond driven gelation of polygalacturonic acid chains