How are polysaccharides and disaccharides digested?

The digestion of carbohydrates takes place in the mouth and the small intestine region of the alimentary canal. The collective name for the enzymes that act on carbohydrates is carbohydrates.

Digestion in the mouth:
As soon as the food enters the mouth, it gets mixed with saliva. Saliva is secreted by the salivary glands that contain a digestive enzyme called salivary amylase. This enzyme salivary amylase is responsible for the breakdown of starch into sugar at pH 6.8.

Salivary amylase continues to act in the oesophagus, but its action stops in the stomach as the contents become acidic. Hence, the digestion of carbohydrates stops in the stomach.

Digestion in the small intestine:
In the small intestine, the digestion of carbohydrates is resumed. As soon as the food enters the small intestine it gets mixed with the pancreatic juice and the intestinal juice. In pancreatic juice, the enzyme pancreatic amylase is present that hydrolyses the polysaccharides into disaccharides.

Similarly, in intestinal juice, a variety of enzymes or disaccharidases such as maltase, lactase, sucrase, etc. are present that helps in the digestion of disaccharides. Thus, in this way, the digestion of carbohydrates is completed in the small intestine.