The Concept of Sugar and Carbohydrates

What is sugar?

Sugar comes under the family of carbohydrates in our food. Carbohydrate is basically compound of carbon, hydrogen, and oxygen. Read also on the harmful effect excess consumption of sugar.

How many types of carbohydrates?

Basically, there are three types of carbohydrate in our food these are:

1.      Monosaccharides/simple sugar

monosaccharides are the simplest form of sugar and the most basic units of carbohydrates. They cannot be further hydrolyzed into simpler chemical compounds. The general formula is C_nH_2nO_n.

How many types of monosaccharides?

There  are three monosaccharides of importance in the body.

                                i.            Glucose (C₆H₁₂O₆)

                              ii.            Fructose

                            iii.            Galactose

What are the sources of monosaccharides?

Glucose is also known as grape sugar and is largely found in fruits, vegetables, and honey.

Fructose is also known as fruit sugar and largely found in fruits and berries. It constitutes over one-third of sugar in honey and is responsible for its sweetness.

Galactose is largely found  as a complex the carbohydrate in milk especially in fermented milk  and the seed coats of legumes

Reason to why simple sugar is absorbed right under the tongue?

After the assimilation in the intestine, all these monosaccharides are finally converted by the liver into glucose so that it is glucose which goes to the body cells for giving energy.

Simple sugar goes into the bloodstream very quickly after being swallowed. They don’t need to undergo a full digestion process that is why some simple sugar can be absorbed right under the tongue.

2.      Disaccharides/compound sugars

A disaccharide  is the sugar formed when two monosaccharides (simple sugars) are joined by glycosidic linkage. Like monosaccharide, disaccharides are soluble in water. The formula is C₁₂H₂₂O_11.

How many types of disaccharides?

The most common type disaccharides are sucrose, lactose, and maltose

        i.            Sucrose is the most common disaccharides also known as white sugar or cane sugar? One molecule of sucrose consists of one molecule of glucose and one molecule of fructose.

Sucrose = glucose +fructose.

A  large source of sucrose is sugarcane and sugar beats 

      ii.            Lactose is known as milk sugar and it makes up half the total solid in milk. It promotes the growth of microorganisms. One molecule of lactose consists of one molecule of glucose and one molecule of galactose. 

Lactose =glucose + galactose.

    iii.            Maltose also known as malt sugar since it is formed in malt by the action of an enzyme called amylase (present in the saliva in the mouth) on starch. It is less sweet than cane sugar but it contains lime, iron, and vitamins all of which are lacking in cane sugar. One molecule of maltose consists of two molecules of glucose.

Maltose =glucose + glucose

A a large source of maltose is sprouting grains, malted wheat, barley and malt extract.

3.      Polysaccharides:

They are made up of many molecules of monosaccharides with the molecular formula as (C₆H₁₀O₅)_n. Types or categories of polysaccharides includes starch, cellulose, glycogen, and dextrins

Why cellulose is not digested by our bodies?

Cellulose which comes from the cell walls of plants is also carbohydrate but is not digested or absorbed by our body because our body doesn’t have enzymes for digesting cellulose. So when cellulose is eaten act as roughage or fibers and help in keeping the intestinal tract in good working order.

When our body uses glycogen?

Glycogen is stored in our body in the liver and muscles and is utilized during periods of excess demand for energy by again getting converted into glucose. Glycogen is the form into which excess glucose is converted to be stored in muscle and liver.

Required and role sugar in the body

Carbohydrates are the main source of energy in the body although not all type of sugar is good for our normal health some sugar is harmful. However, all carbohydrates cannot be absorbed by our bodies as such. During the process of digestion polysaccharides and disaccharides get broken into monosaccharide or simple sugars that are absorbed by the blood. The liver converts all monosaccharides into glucose which is then transferred into the body cells. Glucose is oxidized by the body cell to produce energy for carrying out body processes.

C₆H₁₂O₆  +  6O_{2   →}  6CO₂  +  6H₂O  +  Energy

 Glucose   oxygen    carbon dioxide  water

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