Starch is a nutritional polysaccharide and is the major storage carbohydrate in plants. It is a heteropolyscaccaride composed of two polysaccharides: Amylose and Amylopectin.
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| Starch |
Amylose vs Amylopectin
Amylose
1.It constitutes about 20% of the starch
2. Amylose is a straight chain polymer of D-glucose units
3. The bonding involved is α-1->4 glycosidic linkage
4. With iodine amylose stains blue
5. α and β amylases can hydrolyse amylose
6. more soluble in water
7. Soluble in hot water without swelling
8. Soluble in hot water but does not form starch gel or paste
Amylopectin
1.It constitutes about 80% of the starch
2. Amylopectin is a branched chain polymer of D-glucose units
3. The bonding involved is α-1->4 glycosidic linkage and α-1->6 glycosidic linkage at branch points
4. With iodine amylopectin stains reddish brown
5. α and β amylases can hydrolyse α-1->4 glycosidic linkage but cannot hydolyse α-1->6 glycosidic linkage at branch points of amylopectin
6. less soluble in water
7. Soluble in hot water with swelling
8. Soluble in hot water but form starch gel or paste
