Component of Food

Component of Food

The major nutrients in our food are named carbohydrates, proteins, fats, vitamins and minerals. In addition, food contains dietary fibres and water which are also needed by our body.

Carbohydrates and Fats:

Main Sources of Carbohydrates

There are many types of carbohydrates. The main carbohydrates found in our food are in the form of starch and sugars.

Carbohydrates mainly provide energy to our body. Fats also give us energy. In fact, fats give much more energy as compared to the same amount of carbohydrates. 

Foods containing fats and carbohydrates are also called ‘energy giving foods’. 

Plant Source-Fats

Animal Source -Fats

Proteins :

Proteins are needed for the growth and repair of our body. Food containing proteins are often called 'body building foods'.

Protein: Plant Source

Protein: Animal Source

Vitamins :

Vitamins help in protecting our body against diseases. Vitamins also help in keeping our eyes, bones, teeth and gums healthy.

Vitamins are of different kinds known by different names. Some of these are Vitamin A, Vitamin C, Vitamin D, Vitamin E and K. There is also a group of vitamins called Vitamin B-complex.

• Vitamin A keeps our skin and eyes healthy. 
• Vitamin C helps body to fight against many diseases. 
• Vitamin D helps our body to use calcium for bones and teeth.

Vitamin C source

Vitamin A source

Vitamin B source

Vitamin D source

Minerals :

Minerals are needed by our body in small amounts. Each one is essential for proper growth of body and to maintain good health.

Roughage and Water :

Dietary fibres are also known as roughage. Roughage is mainly provided by plant products in our foods. Whole grains and pulses, potatoes, fresh fruits and vegetables are main sources of  roughage. 

Roughage does not provide any nutrient to our body, but is an essential component of our food and adds to its bulk. This helps our body get rid of undigested food.

Water helps our body to absorb nutrients from food. It also helps in throwing out some wastes from body as urine and sweat. Normally, we get most of the water that our body needs from the liquids we drink — such as water, milk and tea. 

Balanced Diet :

The food we normally eat in a day is our diet. For growth and maintenance of good health, our diet should have all the nutrients that our body needs, in right quantities. Not too much of one and not too little of the other. The diet should also contain a good amount of roughage and water. Such a diet is called a balanced diet.

If the vegetables and fruits are washed after cutting or peeling them, it may result in the loss of some vitamins. The skins of many vegetables and fruits contain vitamins and minerals. Similarly, repeated washing of rice and pulses may remove some vitamins and minerals present in them.

At the same time, cooking also results in the loss of certain nutrients. Vitamin C gets easily destroyed by heat during cooking.

Deficiency:

It can be very harmful for us to eat too much of fat rich foods and we may end up suffering from a

condition called obesity.

A person may be getting enough food to eat, but sometimes the food may not contain a particular nutrient. If this continues over a long period of time, the person may suffer from its deficiency.

Deficiency of one or more nutrients can cause diseases or disorders in our body. Diseases that occur due to lack of nutrients over a long period are called deficiency diseases.

If a person does not get enough proteins in his/her food for a long time, he/she is likely to have stunted growth, swelling of face, discolouration of hair, skin diseases and diarrhoea. 

If the diet is deficient in both carbohydrates and proteins for a long period of time, the growth may stop completely. Such a person becomes very lean and thin and so weak that he/she may not even be able to move.

All deficiency diseases can be prevented by taking a balanced diet.

Some diseases/disorders caused by deficiency of vitamins and minerals

Test for presence of Nutrients :

The tests for presence of carbohydrates, proteins and fats are simpler to do as compared to the tests for other nutrients. For carrying out these tests, you will need solutions of iodine, copper sulphate and caustic soda.

A dilute solution of iodine can be prepared by adding a few drops of tincture iodine to a test tube half filled with water. 

Copper sulphate solution can be prepared by dissolving 2 gram (g) of copper sulphate in 100 millilitre (mL) of water.

10 g of caustic soda dissolved in 100 mL of water makes the required solution of caustic soda.

Test For Starch :

Adding  2-3 drops of dilute iodine solution , A blue-black colour indicates that it contains starch.

Test for protein: 

If the food we want to test is a solid, we first need to make a paste of it or powder it. Grind or mash a small quantity of the food item. Put some of this in a clean test tube, add 10 drops of water to it and shake the test tube. Now, using a dropper, add two drops of solution of copper sulphate and ten drops of solution of caustic soda to the test tube.  

A violet colour indicates presence of proteins in the food item.

Test For Fats:

Take a small quantity of a food item. Wrap it in a piece of paper and crush it. Take care that the paper does not tear. Now, straighten the paper and observe it carefully. 

An oily patch on paper shows that the food item contains fat. 

The food items may sometimes contain a little water. Therefore, after you have rubbed an item on paper, let the paper dry for a while. If there were any water that may have come from food, it would dry up after some time. If no oily patch shows up after this, the food item does not contain any fat.