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HOW ARE POLYSACCHARIDES AND DISACCHARIDES DIGESTED
Disaccharides and polysaccharides must be digested before the body can use them, while monosaccharides do not require digestion.Digestion is both a mechanical process (chewing) and a chemical process (enzymic actions). The class of enzymes that hydrolyze carbohydrates are broadly known as carbohydrases.

While the digestion of all types of foods (proteins, carbohydrates, fats, etc.) begins in the mouth with the mechanical process of mastication, certain carbohydrates—namely, starches and dextrins—are the only food types whose chemical digestion begins in the mouth. Here an enzyme known as salivary amylase or ptyalin, secreted by the parotid glands, is mixed with the food during the chewing process and begins the conversion of glycogen, starch and dextrins into the disaccharide maltose.

Carbohydrates in the chime are hydrolyzed by pancreatic amylase into disaccharides.  Disaccharides and polysaccharides are converted into monosaccharides in the process of digestion, as carbohydrates can be absorbed and assimilated only as monosaccharides. Starch must first be converted into sugar, and the complex sugars must be converted into simple sugars before they are absorbed.


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