The primary difference between starch and cellulose is that starch uses both 1,4 and 1,6 alpha linkages and has a branched structure, while cellulose consists of 1,4 beta linkages and exhibits a rigid, elongated structure.

What is Starch?

Starch is a polysaccharide (C6H10O5)n made up of numerous glucose monomers linked by glycosidic bonds. It is commonly found in seeds, bulbs, and tubers. Starch is a type of carbohydrate, which are organic compounds consisting of carbon, hydrogen, and oxygen, typically in a 1:2:1 ratio. Carbohydrates are a key class of biomolecules.
Iodine can be used to detect starch in foods. When starch is present, the iodine solution, which is orange-yellow, turns blue-black.

Starch serves many functions. Your body breaks down starch into glucose, which provides essential energy for every cell. In the food industry, starch is used to thicken processed foods and to produce sweeteners. Pure starch is a white, tasteless, and odorless powder that does not dissolve in cold water or alcohol. It is made up of two types of molecules: linear and helical amylose, and branched amylopectin.

Typically, starch contains about 20 to 25% amylose and 75 to 80% amylopectin, depending on the plant source. Glycogen, which serves as the energy reserve in animals, is a more extensively branched form of amylopectin.

In industrial processes, starch is frequently converted into sugars, often through malting. These sugars can then be fermented to produce ethanol, which is used in the production of beer, whisky, and biofuels. Additionally, sugars derived from processed starches are commonly used in a wide range of processed foods.

What is Cellulose?

Cellulose is a complex carbohydrate and a major structural component of plant cell walls. It is a polysaccharide made up of long chains of glucose molecules linked together by beta-1,4-glycosidic bonds. These chains form rigid structures that provide strength and rigidity to plant cells.

some important features of cellulose is given below:

1. Structure: Cellulose consists of linear chains of glucose units, which are arranged in parallel and held together by hydrogen bonds. This forms microfibrils that create a strong and rigid network.
2. Insolubility: Cellulose is insoluble in water and most organic solvents due to its strong hydrogen bonding and crystalline structure.
3. Digestibility: Humans cannot digest cellulose because we lack the necessary enzymes to break down the beta-1,4-glycosidic bonds. However, cellulose is an important dietary fiber, which aids in digestion by promoting healthy bowel movements.
4. Uses: Cellulose is used in various applications, including the production of paper, textiles (like cotton and linen), and as a food additive (e.g., to add bulk or texture). It is also used in the manufacture of biodegradable plastics and other materials.
5. Natural Occurrence: It is found abundantly in plant materials, including wood, cotton, and many fruits and vegetables.

Starch vs cellulose

The main difference between starch and cellulose is given below:

Properties	Starch	Cellulose
Glucose Type	Composed of two types of alpha glucose.	Composed of beta glucose.
Linkage	Connected by alpha linkages.	Connected by beta linkages.
Digestibility	Easily digested by humans.	Difficult for humans to digest.
Solubility	Dissolves in warm water.	Insoluble in water.
Strength	Weaker compared to cellulose.	Strong and rigid.
Crystalline Structure	it is less crystalline.	it is more crystalline.
Human Consumption	Can be consumed and used by humans.	Cannot be consumed by humans.
Linkage Type	Alpha 1,4 linkages.	Beta 1,4 linkages.
Function	Used by plants to store energy.	Used by plants for structural support.