Components of Food

By | May 17, 2018

Question 1 Name the nutrients present in our food which give mainly energy to our body?

Question 2 Name the nutrient which is needed for the growth and repair of our body?

Question 3 Name the major nutrients in our food?

Question 4 Name few foods each rich in fats, proteins, carbohydrates, vitamins, minerals?

Question 5 Name the vitamin which is required for maintaining good eyesight?

Question 6 Which vitamin is produced in the human body when skin is exposed to sunlight?

Question 7 What is the function of carbohydrate present in our food?

Question 8 Why vitamins are necessary in our food?

Question 9 State the functions of water in our food?

Question 10 What is roughage?What is the function of roughage in our body?Name the sources of roughage in our food?

Question 11 How will you test the presence of fat in a given food material?

Question 12 How will you test the presence of starch in a given food material?

Question 13 How will you test the presence of protein in a given food material?

Question 14 Why fats and carbohydrates are called energy giving food?

Question 15 What is vitamin B complex?

Question 16 Why do we need calcium in our diet? Name the food items which are rich in calcium?

Question 17 Why do we need iron in our diet? Name the food items which are rich in iron?

Question 18 Why do we need iodine in our diet? Name the food items which are rich in iodine?

Question 19 Define the term nutrients?

Question 20 Name the sources of plant proteins?

Question 21 Name the sources of animal proteins?

A meal consists of Chapatti ,dal ,bhindi, fish curry, vegetables ,curd, butter, milk ,pickles, pulses etc.

A substance which is essential for maintaining life and for growth is called nutrients.

Our food has 5 major nutrients

(1) Carbohydrates

(2) Fats

(3) Proteins

(4) Vitamins

(5) Minerals

Water and roughage are also important parts of our food.

Components of food

Components of food

Our food has 7 components:

(1) Carbohydrates

(2) Fats

(3) Proteins

(4) Vitamins

(5) Minerals

(6) Water

(7) Roughage



They provide energy to our body.

For Example : glucose ,sugar starch( it comes from cereals like wheat and rice)

Wheat –> Chapatti ,bread ,noodles

Rice—> Idli ,Dosa

Potatoes contain a lot of carbohydrates.

Sources of Carbohydrates are wheat, rice, Maize, millet, potato, sweet potato ,sugar, honey, banana ,mango, papaya etc.

Test for presence of starch

The presence of starch in food item can be tested by using a dilute iodine solution.

This test is based on the fact that iodine produces a blue – black colour on combination with starch.

A food items which gives a blue black colour on adding a few drops of dilute iodine solution will contain starch.

A food item which does not produce a blue black colour on adding dilute iodine solution will not contain starch.


1. Take a small quantity of the food to be tested.

2. Add 2-3 drops of dilute iodine solution to the food with a dropper.

3. If a blue black colour is produced then starch is present in the given food.


Fats also provide energy to our body. They provide us twice as much energy as that provided by the same amount of Carbohydrates.

For example: butter ,ghee, milk ,cheese, oil (groundnut ,mustard ,sunflower, coconut), egg yolk, meat ,cashew, soybean.

Fats are solid at room temperature and oils are liquid at room temperature.

Fats as well as carbohydrate provide energy, therefore they are called energy giving food.

Plant sources of fats are groundnut oil ,mustard oil ,coconut oil ,Sunflower oil , til, nuts.

Animal sources of fats are butter, ghee, milk, cheese, eggs ,meat.

Test for fats

A translucent object is one which allows light to pass through it partially.

Fats produce a greasy patch when rubbed on a clean sheet of paper. The greasy patch produced by a fat on paper is translucent which lets some light to pass through it when paper is held towards a source of light. Since some light passes through it, a greasy patch appears to be bright as compared to rest of the paper.


1. Rub a small quantity of the given food in the centre of brown paper.

2. Hold this paper in front of a source of light and look through it.

3. If the food has left a bright greasy patch on paper ,then fat is present in the food.

4. The food item being tested may sometimes contain a little water which may produce a wet patch.So after rubbing the food item on paper, the paper should be allowed to dry for a while.

5. If the greasy patch remains even when the paper is dried then the food item contains fat.



(1) They supply the body with materials to make new cells which build the body and make it grow.

(2) It also give materials which repair the damaged body cells.

Food containing proteins are known as body building foods.

The various foods which are rich in proteins are milk, cheese, pulses ,peas ,beans, fish ,meat, eggs, chicken ,groundnut ,soybean , gram chana ,black gram.

The foods such as pulses, peas, beans ,soybean ,groundnut are good sources of plant proteins.

The foods like milk ,cheese ,fish, chicken ,eggs are main sources of animal proteins.

Test for proteins

Proteins gives a violet colour with an alkaline solution of copper sulphate.

Two solutions are needed for testing proteins: copper sulphate solution and sodium hydroxide solution.

Copper sulphate solution is prepared by dissolving 2 g copper sulphate in 100 ml of water.

Sodium hydroxide is prepared by dissolving 10 grams of sodium hydroxide in 100 ml of water.


1. Take 2ml of the given foodstuff solution or its suspension in a test.

2. Add a little of dilute sodium hydroxide solution till the mixtures clears.

3. Then add two or three drops of copper sulphate and shake the test tube.

4. If a violet colour appears in the solution ,then protein is present in the given food stuff.


Vitamins are necessary for good eye sight ,bones and gums ,healthy teeth ,proper digestion, normal growth.

They help in protecting our body against diseases. They are needed by our body in very small quantities.

Some of the important vitamins are Vitamin A, Vitamin B1 , Vitamin B2 ,Vitamin C ,Vitamin D ,Vitamin E ,Vitamin K ,Vitamin B6 .

Vitamin B1, B2 ,B6 ,B12 are known as Vitamin B complex.

Vitamin A

It is necessary for good eyesight, healthy skin and hairs.

Sources: milk, butter ,carrots ,fish liver oil, mango, papaya, eggs, green vegetables .

Vitamin B

It is essential for growth ,proper functioning of digestive system, heart, nerves ,muscles .

Sources: milk, eggs, meat, wheat, rice ,potatoes , yeast, green vegetables.

Vitamin C

It is necessary for keeping teeth ,gums, joints healthy.

It also increases the resistance of our body to infection and helps to fight diseases.

Sources :Citrus fruits, amla ,tomato, guava, green vegetables.

Vitamin D

It is necessary for normal growth of bones and teeth.

It helps our body to absorb calcium and Minerals from the food.

Sources : milk, fish, butter ,fish liver oil.

Some vitamin D is also made in our body when the skin is exposed to sunlight.


They are needed to build bones and teeth, formation of blood, coagulation of blood, functioning of muscle, nerves and thyroid glands.

Some of the important minerals needed by our body are calcium, phosphorus, iron ,sodium ,potassium, Iiodine.

Sources of calcium

milk ,cheese, eggs, green leafy vegetables ,fish ,wheat ,rice.

Sources of Phosphorus

Milk ,Bajra ,banana, pulses, green leafy vegetables. milk.

Sources of Iodine

Seafood ,vegetable, fruits, iodised salt, drinking water at most of the places.

Iodine is essential for the proper functioning of the thyroid gland which controls the growth of the body.

Sources of Iron

Spinach, leafy vegetables, apples, eggs , cereals, pulses, groundnuts.

Iron is needed to make haemoglobin present in red blood cells (which carries oxygen from the lungs to the body parts)


Water is needed by our body:

(1) To transport digested food to the body cells.

(2) To transport important chemicals such as hormones around the body.

(3) To get rid of waste products from the body.

(4) To control and regulate the temperature of body.

Our body needs 2-3 L of water everyday.


Drinking water , milk , tea, coffee, juice, fresh fruits and vegetables.


It is the fibrous matter in food which cannot be digested.

It is mainly made of an indigestible carbohydrate called cellulose which is present in plant cell wall.

Roughage provides bulk to the food, keeps the food and waste matter moving along the intestine and helps to prevent constipation.

The difficulty in discharging hardened faeces from the body is called constipation.


Fruits, vegetables, wholemeal flour products.

wholemeal flour products: The flour made from entire wheat grains from which bran is not removed.Is product include wholemeal chapatti and wholemeal bread.

One thought on “Components of Food

Leave a Reply

Your email address will not be published. Required fields are marked *