Starch Pasting, Gelatinization and Syneresis Go to Slide Show mode and click to begin
Starch granules contain both linear amylose and branched amylopectin.
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
Gelatinization
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
Syneresis
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.