from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Solidification by cooling or freezing.
- n. The process of forming a gel.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The formation of a solid by cooling; freezing
- n. The formation of a gel, especially from a sol
from the GNU version of the Collaborative International Dictionary of English
- n. The process of becoming solid by cooling; a cooling and solidifying.
from The Century Dictionary and Cyclopedia
- n. The assumption of the solid state by cooling below common atmospheric temperature; freezing.
This temperature is called the gelation range, because the granules become individual gels, or water-containing meshworks of long molecules.
When a starchy cereal is cooked, water penetrates the granule and separates the chains from each other, thus swelling and softening the granule in the process called gelation center.
They've also shown that their cooking, in Adria's case often labeled "molecular gastronomy," can illustrate scientific feats such as spherification, gelation and oxidation.
It competes with the flour starch for water, and raises the starch gelation temperature nearly to the boiling point: so it adds hardness and crispness.
Root and tuber starches contain a fraction of the lipids and proteins that are associated with cereal starches, which makes them more readily gelated— lipids delay gelation by stabilizing granule structure—and gives them less pronounced flavors.
As the sauce heats up and the temperature reaches the gelation range, the granules absorb water and swell, and the sauce consistency begins to thicken center.
Cooling Reorganizes Starch Molecules and Firms Granules Once the cooking is finished and the seeds cool down below the gelation temperature, the starch molecules begin to re-form some clusters with pockets of water in between, and the soft, gelated starch granules begin to firm up again.
Leftover rice is often hard due to the retrogradation of the starch, which is cured by heating it up to the gelation temperature again.
Thickening: The Granules Leak Starch Depending on how concentrated the starch granules are to begin with, the starch-water mixture may noticeably thicken at various points during their swelling and gelation.
Rice noodles are made by soaking high-amylose rice in water, grinding it into a paste, cooking the paste so that much but not all of the starch is gelated, kneading the paste into a dough and extruding it to form noodles, steaming the noodles to finish the gelation process, cooling and holding for 12 hours or more, and drying with hot air or by frying them in oil.