Components of food

The topic, Components of food is mentioned in the CTET paper 2 science syllabus. This topic is directly taken from class 6 NCERT science book. It is the 2nd chapter of this book. I have covered all the important details from this chapter at examination prospective but If you want to read that complete chapter, you can download the PDF given at the end of this article.

Nutrients: These are the essential substances in food that our bodies need to grow, stay healthy, and get energy. They are like building blocks that help our bodies work properly. There are five main types of nutrients:

Carbohydrates
Proteins
Fats
Vitamins
Minerals

Carbohydrates

Carbohydrates are a type of nutrient that supplies energy to our bodies. They are like fuel, helping us move, play, and think. Carbohydrates are mainly found in plant-based foods, including grains like rice and wheat, starchy vegetables like potatoes, and fruits.

Carbohydrates can be classified into two main types:

Simple Carbohydrates: These are quick-energy sugars found in foods like fruits, milk, and sweets. They are easy for the body to break down, so they provide a fast boost of energy.
Complex Carbohydrates: These are starches and fibers that take longer to digest, giving steady energy over time. Foods like pasta, bread, beans, and vegetables contain complex carbohydrates.

Carbohydrates are important for keeping us active and are the primary energy source for both our muscles and our brain.

Test for Starch

There are many types of carbohydrates. The main carbohydrates found in our food are in the form of starch and sugars. We can easily test if a food item contains starch.

Take a small quantity of a food item or a raw ingredient. Put 2-3 drops of dilute iodine solution on it. Observe if there is any change in the colour of the food item. Did it turn blue-black?

A blue-black colour indicates that it contains starch.

Proteins

Proteins are defined as essential nutrients that are crucial for the growth and repair of the body. They are made up of smaller units called amino acids, which are linked together in different combinations to form various proteins. Proteins serve multiple important functions in the body:

Building and Repairing Tissues: They help in the development of muscles, skin, and organs.
Enzymes: Many proteins function as enzymes, which accelerate biochemical reactions that are necessary for digestion and other processes.
Hormones: Some proteins act as hormones, regulating various bodily functions, such as metabolism and growth.
Immune System: Proteins are vital for the immune system, producing antibodies that help defend the body against infections and diseases.
Transport: Proteins assist in transporting important substances throughout the body, like oxygen, through hemoglobin in red blood cells.

Sources of protein include animal-based foods such as meat, fish, eggs, and dairy products, as well as plant-based sources like beans, lentils, nuts, and seeds. A balanced diet that includes sufficient protein is essential for maintaining health and supporting bodily functions.

Test for Proteins

A simple method to test for the presence of proteins in food using what is commonly known as the Biuret Test. This test requires a food sample, copper sulfate solution, and sodium hydroxide solution.

To begin, a small portion of the food sample, such as milk or pulses, is placed in a test tube. Next, 2-3 drops of copper sulfate solution are added, followed by 10 drops of sodium hydroxide solution. The test tube is then gently shaken to mix the contents.
If the food contains protein, a violet or purple color will appear, indicating a positive result.

Fats

Fats are also known as lipids and are an important part of a balanced diet. They serve several key functions in the body:

Energy Source: Fats are a rich source of energy, providing more than twice the amount of energy per gram compared to carbohydrates and proteins.
Storage: The body stores excess energy as fat, which can be used when needed. This helps to maintain energy levels during times when food intake may be low.
Insulation and Protection: Fats help insulate the body, keeping it warm, and they also protect vital organs by providing a cushioning effect.
Cell Structure: Fats are essential components of cell membranes, helping to maintain their structure and function.
Nutrient Absorption: Fats aid in the absorption of fat-soluble vitamins (A, D, E, and K), which are important for various bodily functions.

Fats can be classified into two main types:

Saturated Fats: These are usually solid at room temperature and are found in animal products (like butter and meat) and some plant oils (like coconut oil).
Unsaturated Fats: These are typically liquid at room temperature and are found in oils from plants (such as olive oil and sunflower oil) and fish.

In the context of a healthy diet, it is important to consume fats in moderation and focus on unsaturated fats for better health.

Test for Fats

The grease spot test is a simple way to check for the presence of fats in food. To perform this test, you need a piece of paper and a small portion of the food sample to be tested. First, take the food sample and rub it onto the paper. Then, let the paper dry for a few minutes. After drying, hold the paper up to light.

If you see a translucent, greasy spot, this indicates the presence of fat in the food sample. If there is no greasy spot and the paper looks unchanged, the sample likely contains little or no fat.

Vitamins

vitamins are defined as organic compounds that are essential for the proper functioning of the body. They play crucial roles in various bodily processes, including metabolism, immunity, and overall health. Vitamins are needed in small amounts and are obtained primarily from the food we eat, as the body cannot produce them in sufficient quantities.

Vitamins can be categorized into two main types:

Water-Soluble Vitamins: These vitamins dissolve in water and are not stored in the body. They need to be consumed regularly in the diet. Examples include:
- Vitamin C: Important for the immune system and skin health, found in citrus fruits, strawberries, and bell peppers.
- B Vitamins: A group that includes several vitamins (like B1, B2, B3, B6, B12, and folic acid) that help convert food into energy and are important for brain function.
Fat-Soluble Vitamins: These vitamins dissolve in fats and can be stored in the body’s fatty tissues. Examples include:

Vitamin A: Essential for vision and immune function, found in carrots, sweet potatoes, and leafy greens.
Vitamin D: Important for bone health and calcium absorption, obtained from sunlight and found in fortified foods and fish.
Vitamin E: Acts as an antioxidant, helping protect cells from damage, found in nuts, seeds, and green leafy vegetables.
Vitamin K: Important for blood clotting and bone health, found in green leafy vegetables and certain oils.

Minerals

Minerals are defined as inorganic nutrients that are essential for the proper functioning of the body. They play a crucial role in various physiological processes and help maintain overall health. Unlike vitamins, minerals are not organic compounds, and they do not provide energy. However, they are vital for several bodily functions, including:

Building Strong Bones and Teeth: Minerals like calcium and phosphorus are essential for the development and maintenance of healthy bones and teeth.
Regulating Body Functions: Minerals help regulate various bodily functions, such as fluid balance, nerve transmission, and muscle contraction. For example, sodium and potassium are important for maintaining fluid balance and proper muscle function.
Supporting Metabolism: Certain minerals act as cofactors for enzymes, aiding in metabolic processes. For instance, zinc is crucial for the activity of many enzymes involved in digestion and metabolism.
Formation of Blood: Minerals such as iron are vital for the production of hemoglobin, the protein in red blood cells that carries oxygen throughout the body.

Common minerals include:

Calcium: Found in dairy products, leafy greens, and nuts; important for bone health.
Iron: Found in red meat, beans, and spinach; essential for oxygen transport in the blood.
Potassium: Found in bananas, oranges, and potatoes; helps regulate fluid balance and muscle contractions.
Sodium: Found in table salt; necessary for maintaining fluid balance and proper nerve function.

Dietary fibers

Dietary fibers (also known as roughage) are defined as the indigestible parts of plant-based foods that play an important role in the digestive system. Although they do not provide nutrients or energy, dietary fibers are essential for maintaining a healthy digestive tract and promoting regular bowel movements.

Key Points About Dietary Fibers:

Sources of Dietary Fibers: Dietary fibers are found in foods like fruits, vegetables, whole grains, pulses, and seeds. Foods high in fiber include apples, carrots, oats, and brown rice.
Promoting Digestion: Fiber adds bulk to the stool, making it easier to pass and preventing constipation.
Helping with Satiety: Fiber-rich foods often make us feel full, which can help in maintaining a healthy weight by reducing overeating.
Reducing Health Risks: A diet high in fiber is associated with a lower risk of certain health issues, such as heart disease and diabetes.

In summary, while dietary fibers do not directly nourish the body, they are essential for a balanced diet and contribute to overall health by supporting digestion and preventing digestive issues.

Balanced Diet

A balanced diet is defined as a diet that provides all the essential nutrients the body needs in the right proportions. It includes a variety of foods to ensure that individuals receive an adequate amount of carbohydrates, proteins, fats, vitamins, and minerals, which are necessary for growth, development, and overall health.

Deficiency diseases are defined as diseases that occur due to a lack of essential nutrients in a person's diet. When the body does not receive adequate amounts of vitamins, minerals, or other nutrients over time, it can lead to various health problems or diseases. Each deficiency disease is linked to a specific nutrient that the body lacks.

Summery

The major nutrients in our food are carbohydrates, proteins, fats, vitamins and minerals. In addition, food also contains dietary fibres and water.
Carbohydrates and fats mainly provide energy to our body.
Proteins and minerals are needed for the growth and the maintenance
of our body.
Vitamins help in protecting our body against diseases.
Balanced diet provides all the nutrients that our body needs, in right quantities, along with adequate amount of roughage and water.
Deficiency of one or more nutrients in our food for a long time may cause certain diseases or disorders.