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Biochemistry & Polymer Chemistry

Starch

The storage polysaccharide of plants, consisting of amylose and amylopectin.

Formula / equation (C₆H₁₀O₅)ₙ
Unit Dimensionless

In depth

Amylose is an unbranched helical chain of alpha-1,4-linked glucose, while amylopectin adds alpha-1,6 branches every twenty-five units or so. The alpha linkage is readily hydrolysed by amylase, which is why starch is digestible while cellulose is not.

Examples in the real world

Potatoes, rice and wheat; the blue-black colour with iodine arises from triiodide trapped in the amylose helix.