Fundamentals of Food Technology

III) Polysaccharides

Starch occurs in the vegetable kingdom. The important sources of starch are
i)Cereals and millets (65-85 per cent)
ii)Roots and tubers (19-35 per cent)


Starch occurs in the form of granules which have characteristic shapes when seen under microscope.
Starch is a polysaccharide formed in nature by the condensation of a large number (4000-15000) of glucose molecules.

It consists of a minute of two components called amylose and amylopectin, one molecule of amylose contains 500-5000 glucose molecules while one molecule of amylopectin contains 50,000-500000 glucose molecules.


Dextrins
Dextrins are polysaccharides formed by the partial hydrolysis of starch by acids or amylase.

Glycogen
Glycogen is the reserve carbohydrate found in liver (3-7 per cent) and muscle (0.5-1 per cent) of animals and man