Where does this come from, and can I check it?

Gelatinised starch re-crystallises as it cools, firming the potato up. The figure is taken from USDA, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a food fact?

Yes. It sits on the Food shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Cooling cooked potatoes changes their starch

Gelatinised starch re-crystallises as it cools, firming the potato up

Heat swells starch granules and lets them absorb water, but cooling lets the amylose chains pack back together in a process called retrogradation. That is why a potato salad firms in the fridge and why reheated potatoes taste denser. The change is reversible only partly, even with more heat.

Where this comes from

USDA

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

Go further

Food & Cooking trivia Science trivia

More facts like this

Waxy potatoes hold their shape and floury ones crumbleThe ratio of amylose to amylopectin starch sets how a potato behaves Good gnocchi depends on dry potato and little flourExtra flour makes the dough springy and the dumplings heavy A green potato has been making chlorophyll and solanineLight turns potatoes green and also raises bitter glycoalkaloids in the skin Risotto creaminess comes from surface starchStirring short-grain rice rubs starch off the grains into the liquid Bread goes stale because its starch re-crystallisesStaling is chemistry in the crumb, not simply water evaporating Starch ratio determines whether cooked rice is fluffy or stickyHigh amylose content yields firm separate grains while amylopectin causes stickiness

Tags: starch, potatoes, cooling

Cooling cooked potatoes changes their starch: the short answers

Where does this come from, and can I check it?: Gelatinised starch re-crystallises as it cools, firming the potato up. The figure is taken from USDA, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a food fact?: Yes. It sits on the Food shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.