Components of the Food
Points to Remember
   Our meal consists of at least one item made by some kind of grains, daal, or a dish of meat or a vegetable.
   Sometimes it may include items like curd, buttermilk, pickle, salad, etc.
   There is variety in the food that we eat.
   Sometimes, we may not really have all this variety in our meals. If we are traveling, we may eat whatever is available on the way.
   The ingredients in the food contain some components that are needed by our body. These components are called nutrients.
   The major nutrients in the food are carbohydrates, proteins, fats, vitamins and minerals.
   In addition to the nutrients, the food contains dietary fibres and water which are also needed by our body.
With some simple methods, we can test whether cooked food or a raw ingredient contains one or more of these nutrients.
   Materials required for carrying out these tests are solutions of iodine, copper sulphate and caustic soda, few test tubes and a dropper.
   There are many types of carbohydrates. The main carbohydrates found in the food are in the form of starch and sugars.
   Test for starch: Put 2-3drops of dilute iodine solution on the food item. A blue-black colour indicates that it contains starch.
   Test for proteins: If the food you want to test is solid, you first need to make a paste of it or powder it. Put some of this in a test tube, add 10 drops of water, and shake the test tube. Using a dropper add two drops of a solution of copper sulphate and ten drops of caustic soda to the test tube. Shake it well. A violet colour indicates the presence of proteins.
   Test for Fats: Take a small quantity of a food item. Wrap it in a piece of paper and crush it. An oily patch on the paper shows that the food item contains fat.
Carbohydrates, proteins and fats are present in all the food items.
   A food item contains more than one nutrient.
   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. Food containing fats and carbohydrates are also called ‘energy-giving foods’.
   Sources of carbohydrates: Sweet potato, potato, sugarcane, papaya, melon, mango, maize, rice, wheat, bajra etc.
   Sources of fats:
   i). plant sources – groundnuts, coconut oil, nuts, til,
   ii). Animal sources – fish, eggs, meat, ghee, milk, butter
   Proteins are needed for the growth and repair of our body. Foods containing proteins are often called ‘bodybuilding foods’.
   Sources of proteins:
   i). plant sources – gram, moong, tur dal, beans peas, soybeans
   ii). Animal sources – fish, eggs, meat, milk, paneer
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   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. 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 the body to fight against many diseases.
   Vitamin D helps our body to use calcium for bones and teeth.
   Vitamins sources
   Vitamin A: Papaya, carrot, mango, milk, fish oil
   Vitamin B: Liver, wheat, rice
   Vitamin C: Orange, green chilli, guava, lemon, amla, tomato
   Vitamin D: Liver, fish, egg, butter, milk
   Minerals are needed by our body in small amounts.
   Minerals sources
   Iodine: Ginger, fish, iodized salt, dairy products
   Phosphorous: Milk, banana, fish, egg
   Iron: Apple, peas, red meat, spinach
   Calcium: Milk, eggs, dairy products
   Rice has more carbohydrates than other nutrients. Therefore, we say that rice is a carbohydrate-rich source of food.
   Besides, nutrients our body also needs dietary fibres and water. Dietary fibre is also known as roughage. Roughage is mainly provided by plant products in our foods.
   Whole grains, pulses, potatoes, fresh fruits and vegetables are the main sources of roughage.
   Roughage 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 the body as urine and sweat,
   For growth and maintenance of good health, our diet should have all the nutrients that our body needs, in the right quantities. The diet should also contain 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 lose some vitamins.
   The skins of many vegetables and fruits contain vitamins and minerals.
   Repeated washing of rice and pulses may remove some vitamins and minerals present in them.
   Cooking improves the taste of food and makes it easier to digest. At the same time, cooking also results in the loss of certain nutrients.
   Many useful proteins and considerable amounts of minerals are lost if excess water is used during cooking and is then thrown away.
   Vitamin C gets easily destroyed by heat during cooking.
It can be very harmful to us to eat too many fat-rich foods and we may end up suffering from a condition called obesity.
   Deficiency Diseases:
   The deficiency of one or more nutrients can cause diseases or disorders in our body. Diseases that occur due to a lack of nutrients over a long period are called deficiency diseases.
nutrients deficiency diseases
   Proteins: Stunted growth, swelling of face, discoloration of hair, skin diseases and diarrhea.
   Carbohydrates and proteins: Growth stops permanently
   Vitamin A: Loss of vision
   Vitamin B1: Beriberi
   Vitamin C: Scurvy
   Vitamin D: Rickets
   Calcium: Bone and tooth decay
   Iodine: Goiter
   Iron: Anemia
Exercise:
1). Name the major nutrients in our food.
   Carbohydrates, proteins, fatty acids, vitamins and minerals are the major nutrients in our food.
2). Name the following.
a). The nutrients which mainly give energy to our body.
   Carbohydrates and Fats.
b). The nutrients that are needed for the growth and maintenance of our body.
   Proteins and minerals.
c). A vitamin required for maintaining good eyesight.
   Vitamin A.
d). A mineral that is required for keeping our bones healthy.
   Calcium.
3). Name two foods rich in
a). Fats
   Butter, ghee.
b). starch
   Rice, sweet potato.
c). Dietary fibre
   Spinach, cabbage.Â
d). protein
   Milk, eggs
4). Tick (√) the statement that is correct.
a). By eating rice alone, we can fulfill the nutritional requirements of our body.  Â
X
b). Deficiency diseases can be prevented by eating a balanced diet. Â
√
c). Balanced diet for the body should contain a variety of food items.
√
d). Meat is alone is sufficient to provide all nutrients to the body.
X
5). Fill in the blanks.
a). Rickets is caused by deficiency of Vitamin D.
b). Deficiency of Vitamin B1 causes a disease is known as beri-beri.
c). Deficiency of Vitamin C causes a disease known as Scurvy.
d). Night blindness is caused due to deficiency of Vitamin A in our food.
Additional Questions:
Fill in the blanks
1). The main carbohydrates found in the food are in the form of starch and sugars.
2). A blue-black colour indicates that it contains starch.
3). A violet colour indicates the presence of proteins.
4). An oily patch on the paper shows that the food item contains fat.
5). Carbohydrates mainly provide energy to our body.
6). Fats also give us energy.
7) Vitamins help in protecting our body against diseases.
8). There is also a group of vitamins called Vitamin B-Complex.
9). Rice is a carbohydrate-rich source of food.
10). Dietary fibre are also known as roughage.
11). Roughage helps our body get rid of undigested food.
12). Most food items usually have more than one nutrients.
13). All deficiency diseases can be prevented by taking a balanced diet.
Write whether True or False.
1). All the foods contain all the nutrients.
   False
2). The tests for the presence of nutrients are complex.
   False
3). Violet colour indicates the presence of carbohydrates.
   False
4). Proteins provide us with energy.
   False
5). Blue-black colour indicates the presence of carbohydrates.
   True
6). Minerals are not essential for our body.
   False
7). A food item contains only one nutrient.
   False
8). Vitamin C helps body to fight against many diseases.
   True
9). Minerals are needed by our body in large amounts.
   False
10). Rice is a carbohydrate-rich source of food.
   True
11). We get the water needed by our body only from the liquids we drink.
   False
12). One can eat a balanced diet only with expensive food items.
   False
13). Eating the right kind of food is enough.
   False
14). All deficiency diseases can be prevented by taking a balanced diet.
   True
Answer the following questions.
1). What are the materials required for testing the presence of nutrients in the food?
   For carrying out the tests for nutrients, we need solutions of iodine, copper sulphate and caustic soda, few test tubes and a dropper.
2). Name the main carbohydrates?
   The main carbohydrates are starch and sugar.
3). Write the importance of proteins.
   Proteins are needed for the growth and repair of our body.
4). Write the use of
i). Vitamins
   Vitamins help in protecting our body against diseases. Vitamins also help in keeping our eyes, bones, teeth and gums healthy.
ii). Water
   Water helps our body to absorb nutrients from food. It also helps in throwing out some wastes from the body as urine and sweat.
iii). Roughage
   Dietary fibres are known as roughage. Roughage is mainly provided by the plant products in our foods. 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.
5). What is a balanced diet?
   The diet that provides all the nutrients that our body needs in the right quantities, along with an adequate amount of roughage and water is called a balanced diet.
6). Write a note on the wastage of nutrients.
   If the vegetables and fruits are washed after cutting or peeling off them, it may result in the loss of some vitamins. Repeated washing of rice and pulses may remove some vitamins and minerals present in them. Many useful proteins and considerable amounts of minerals are lost if excess water is used during cooking and is then thrown away.
7). What is meant by deficiency disease?
   Diseases that occur due to a lack of nutrients over a long period are called deficiency diseases.
8). Name the types of Vitamins.
   Various types of Vitamins are Vitamin A, Vitamin B-Complex, Vitamin C, Vitamin D, Vitamin E and K.
Give reasons
1). Carbohydrates and fats are energy-giving foods.
   Carbohydrates mainly provide energy to our body. Fats also give us energy. Therefore, food containing fats and carbohydrates are also called ‘energy-giving foods’.
2). Proteins are body-building foods.
Proteins are needed for the growth and repair of our body. Therefore they are body-building foods.
3). Rice is a carbohydrate-rich source of food.
Rice has more carbohydrates than other nutrients. Therefore it is a carbohydrate-rich source of food.
4). Roughage does not provide any nutrients to our body but is an essential component of food.
Match the following
i). Vitamin AÂ Â Â Â Â Â Â Â Â Â a. rickets
ii). Vitamin BÂ Â Â Â Â Â Â Â Â Â b. scurvy
iii). Vitamin CÂ Â Â Â Â Â Â Â Â c. loss of vision
iv). Vitamin DÂ Â Â Â Â Â Â Â Â d. beriberi
Answers:
i). Vitamin A – loss of vision
ii). Vitamin B – beriberi
iii). Vitamin C – scurvy
iv). Vitamin D – rickets
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