Starch Gelatinization and Pasting, Gelation, and Uglification Go to Slide Show mode and click to begin

Starch granules contain both linear amylose and branched amylopectin.

Timeline You are here Turn heat on

Raw, uncooked starch granules heated in water

Swelling is evident

Notice loss of amylose from the granules

Gelatinization and pasting are complete Some granules have collapsed. Gelatinization and pasting are complete

Timeline gelatinization You are here Turn heat off Start to cool

Gelation

Now we start to cool.

Notice areas of association. These are called junction zones.

This picture is not yet complete as we haven’t accounted for the water in the system.

water This is a starch gel

Timeline gelatinization gelation You are here Ideal texture

Uglification

WATER This picture ignores swollen and collapsed granules. Junction zones will naturally enlarge over time or in response to processes such as freezing.

+ WATER of SYNERESIS that has been squeezed out of the gel structure The texture gets very ugly when this happens.

Timeline gelatinization gelation uglification You are here Ugly texture Syneresis