Starch
Starch is a complex carbohydrate that is found in many plant-based foods. It is the most common carbohydrate in the human diet and serves as a major source of energy for the body. Starch is composed of long chains of glucose molecules, which are linked together in a specific way to form a structure that can be broken down by enzymes in the body.

Types of Starch
There are two main types of starch: amylose and amylopectin. Amylose is a linear chain of glucose molecules, while amylopectin is branched. The ratio of amylose to amylopectin in a starch molecule can affect its properties, such as its gelatinization temperature and viscosity.

Sources of Starch
Starch is found in a variety of plant-based foods, such as grains (wheat, rice, corn), tubers (potatoes, cassava), and legumes (beans, lentils). These foods are important sources of carbohydrates in the human diet and provide energy for various metabolic processes in the body.

Functions of Starch
- Energy source: Starch is a major source of energy for the body. When consumed, it is broken down into glucose, which is then used by cells for energy production.
- Thickening agent: Starch can be used as a thickening agent in cooking and food processing. When heated in the presence of water, starch granules swell and absorb water, thickening the surrounding liquid.
- Structure: Starch can also provide structure to foods, such as in baked goods, by forming a network that helps maintain the shape and texture of the final product.

Digestion of Starch
Starch digestion begins in the mouth, where an enzyme called salivary amylase starts breaking down starch into smaller molecules. In the small intestine, pancreatic amylase continues the digestion process, breaking starch down into maltose and other sugars that can be absorbed by the body.
In conclusion, starch is a vital component of the human diet, providing energy and serving various functions in food preparation and processing. Its digestion is a complex process involving specific enzymes and plays a crucial role in providing the body with a source of glucose for energy production.