Stabilization
Another important starch modification is that of stabilization. This modification prevents gelling
and weeping and maintains textural appearance.
Earlier, it was mentioned that the linear fraction of cooked corn starch will reassociate
through hydrogen bonding causing gelling, opacity and weeping. Since the highly branched
waxy variety has no amylose, it will not retrograde or gel under normal storage conditions.
However, under low-temperature or freezing conditions, a waxy paste will become cloudy and
chunky and will weep, somewhat like the paste made with regular corn starch. This is attributed
to a lowering of kinetic movement as the temperature drops, allowing the outer branches of the
waxy starch to associate through hydrogen bonding and bringing about similar but less dramatic
conditions that occur with amylose.
To prevent the occurrence of this condition, anionic groups are scattered throughout the granule
to block molecular association through ionic repulsion as well as steric hindrance. (Fig. 11).
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