Why does corn starch dissolve in cold water but gets clumpy in warm water?

152 views

Why does corn starch dissolve in cold water but gets clumpy in warm water?

In: 2

2 Answers

Anonymous 0 Comments

Starches become a sort of “gel” when they get warm. Which is why we often use it as a sauce thickener. This is also the same reason why popcorn and Cheeto puffs exist.

The reason why starches gelatinize in hot water has to do with a bunch of complicated physical processes that you can learn about here

https://en.m.wikipedia.org/wiki/Starch_gelatinization

Anonymous 0 Comments

Starches form a gel when warm and wet, which makes them useful as thickeners. However if you drop a lump of starch in hot water the outside of the lump turns to gel first and protects the interior, still powdered, starch. The annoying bit is if you simply try to stir or break up the clump, you keep exposing new starch to the hot water to form new gel layers, getting you nowhere. For this reason in recipes you either want to mix starch into cold water before adding it to whatever how liquid you have, or carefully sprinkle it in a little at a time to give it time to dissolve before gelling.