Components of Food PDF

NOTES CHAPTER – COMPONENTS OF FOOD INTRODUCTION Food is required for our good health, maintenance, growth, and development. IMPORTANCE OF FOOD  For proper growth and development o...

NOTES CHAPTER – COMPONENTS OF FOOD INTRODUCTION Food is required for our good health, maintenance, growth, and development. IMPORTANCE OF FOOD  For proper growth and development of the body.  For providing energy to perform various activities like walking, talking, etc.  For performing various body functions and life processes.  For repairing damaged or injured body cells.  For protecting against diseases and infections. NUTRIENTS – Components of food which are needed by us for growth, development and maintenance of our body are called nutrients. MAJOR COMPONENTS OF FOOD :- o Major nutrients in our food are carbohydrates, proteins, fats, vitamins and minerals. o In addition, food contains dietary fibers and water which are also needed by our body. Different Type of Food Energy- Food containing Carbohydrates and Fats. Carbohydrates provide us instant energy. Fats are giving food stored energy resources. Fats give much more energy as compared to the same amount of carbohydrates. Body- Proteins are body-building food as they help in body growth and repair of damaged parts of building the body. food Vitamins and minerals are protective food as they protect us from many diseases. They give Protective us resistance against disease causing germs and are importance for growth and maintaining food healthy body. Carbohydrates  Provides energy to our body.  The main carbohydrates found in our food are in the form of starch and sugars.  Some SOURCES of carbohydrates are wheat, rice, bajra, maize, potato, sweet potato, sugarcane, jaggery (gud),honey, fruits (melon, mango and papaya), etc. These are ‘carbohydrate rich’ source of food.  The carbohydrates in our food are obtained mainly from plant sources. Q1. How will you TEST for the presence of starch in a food item? Answer: Take a small quantity of a food sample, put 2-3 drops of iodine solution on it. A blue black colour indicates that the food sample contains starch. Fats  Provides energy to our body.  Fats are the slowest source of energy but the most energy-efficient form of food.  Each gram of fat supplies the body with calories, more than twice that supplied by equal amount of proteins or carbohydrates.  Food containing both carbohydrates and fat are called ‘ENERGY GIVING FOODS’  There are generally two types of SOURCES of fats: Plant & Animal o Plant source: Ground nut oil, mustard oil, sunflower oil, coconut oil, cashew, nuts, til, groundnut o Animal source: Butter, ghee, milk, cream, cheese, egg, meat, fish. Excess body fat leads to a condition called Obesity. Obesity may lead to heart diseases. Q2. How will you TEST for fat in a food sample? Answer: Put the sample of food on a piece of paper and crush it. If the paper at that spot becomes translucent and greasy, the sample contains fat. Proteins  Protein is needed for growth and repair of our body.  Food containing proteins are called ‘BODY BUILDING FOODS’  Children require more protein because of the rapid growth of their body.  There are generally two types of SOURCES of Protein: Plant & Animal o Plant source: Gram, moong, dal, beans, soyabeans, peas o Animal source: Milk, paneer, fish,meat,eggs Q3. How will you TEST for protein in a food sample? Answer: Take a small quantity of food sample in a test tube, add 10 drops of water to it and shake the test tube, after that add two drops of solution of copper sulphate and ten drops of caustic soda. A violet colour indicates presence of protein in the food sample. S. NO. NAME OF NUTRIENT SOURCES 1 CARBOHYDRATES Plant source – rice , bajra, maize, wheat , bread , mango , potato, sweet potato, papaya, melon, sugarcane, jaggery(gud),honey 2. FATS Plant source – coconut oil , nuts , mustard oil, soyabean oil, sunflower oil, groundnuts, til Animal source – milk, butter , cream , fish , eggs , ghee, cheese,meat 3. PROTEINS Plant source – soyabean , peas , gram , moong , pulses, beans Animal source – meat , fish , milk , eggs , paneer Vitamins For proper functioning of our body, we need all types of vitamins in our diet in small quantities. Vitamins keep us healthy. 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.  Vitamins are of two types: FAT-SOLUBLE (Vitamin A, D, E, K) and WATER-SOLUBLE (Vitamin B,C).  Lack of vitamins in the body can cause deficiency disease. S NO. NAME OF VITAMIN SOURCES 1. VITAMIN A Plant source – papaya , carrot , mango Animal source – milk , fish oil 2. VITAMIN B Plant source – wheat , rice Animal source - liver 3. VITAMIN C Plant source –tomato, guava, orange, lemon, amla(all citrus fruits ) 4. VITAMIN D Animal source – milk , butter , fish , eggs , liver 5. VITAMIN E Plant source – almonds , walnuts , sesame seeds , flax seeds Animal source – fish oil 6. VITAMIN K Green leafy vegetables Minerals  They are required in small quantities in our diet.  Their deficiency also leads to deficiency diseases. S NO. NAME OF MINERAL SOURCES 1. IRON Plant source – spinach , pear , apple Animal source - liver 2. IODINE Plant source – spinach , ginger Animal source – fish , prawns , crab Natural source - salt 3. PHOSPHORUS Plant source – banana , green chilli , rice , wheat Animal source - milk 4. CALCIUM Milk , eggs Roughage (Dietary Fiber) Roughage is the fibrous material present in food which cannot be digested. Functions if Roughage:  Roughage does not provide any nutrient to our body, but is an essential component of our food and adds to its bulk.  Roughage helps our body to get rid of undigested food. Main source of roughage: Whole grains, pulses, potatoes, fresh fruits and vegetables. It is mainly provided by plant products in our foods. Water  Water makes up almost 70% of our body weight and various life processes are impossible without it.  We take in water not only directly by drinking, but also as part of the food we eat.  Fresh fruits and vegetables also provide a lot of water to our body, e.g. tomatoes, spinach, oranges, water melons, etc.  It helps our body to absorb nutrients from food.  It also helps in throwing out some wastes from the body as urine and sweat.  It controls our body temperature and keeps our body cool, clean and healthy. Balanced Diet The diet that contains the right amount of all nutrients, a good amount of roughage and water to meet our body needs is called a Balanced Diet.  A balanced diet provides the body with all energy and fulfils various nutrient requirements needed for proper functioning. A balanced diet should include the foods that are  Energy rich fats and carbohydrates like butter, rice and chapatis.  Body building Proteins, pulses and peas.  Protective Vitamins, minerals, vegetables and fruits. Loss of Nutrients in Food  Eating the right kind of food is not enough. It should also be cooked properly so that its nutrients are not lost.  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.  Repeated washing of rice and pulses may remove some vitamins and minerals present in them.  Cooking 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.  Hence, it is important to include some fruits and raw vegetables in our diet. Deficiency Diseases  A person may be taking a good amount of food, but if he does not take one or two nutrients for a long time, the person may suffer from its deficiency, which may result in deficiency disease in that person.  Diseases which occur due to lack of specific nutrients in the diet over a long period of time, are called deficiency diseases. Examples deficiency diseases caused by deficiency of Carbohydrates and Proteins  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, discoloration of hair, skin diseases and diarrhea.  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. Q4. Why Vitamin D deficiency is observed among many people nowadays? Ans: Our body prepares Vitamin D in the presence of sunlight. Nowadays, insufficient exposure to sunlight is causing Vitamin D deficiency in many people. Example Of Deficiency Diseases caused by deficiency of Vitamins and Minerals :