Understand the roles of Carbohydrates, Fats, and Proteins, and learn the laboratory tests used to detect them in food.
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Hook on carbohydrates providing instant energy.
Explain the iodine test for starch.
Starch is a common type of carbohydrate found in our diet, especially in foods like potatoes, rice, and bread. We can detect its presence using a simple chemical test in the laboratory.
Visual of dropping iodine on a potato.
Adding diluted iodine solution to a starch-rich food like potato results in a blue-black color change.
Fill in the blanks regarding carbs and the starch test.
Carbohydrates are -giving foods that provide fuel for our daily activities. Cereals like wheat, rice, and maize are primary sources of carbohydrates, and common sugar is also a type of this nutrient. Starch is a complex form of carbohydrate found in foods like potato and boiled rice. To test for the presence of starch in a food item, we can perform a simple laboratory experiment. The procedure involves adding 2–3 drops of diluted solution to the food sample. If the food item changes its color to , it confirms that starch is present. Understanding these basic helps us make informed dietary choices to stay active and healthy.
Explain fats as stored energy and how to test for them.
Like carbohydrates, fats are also energy-giving foods. However, fats act as a source of stored energy and actually provide much more energy than the same amount of carbohydrates.
MCQ on the fat test.
A student wants to find out if a handful of crushed peanuts contains fat. What is the simplest and most accurate way to test this?
Summary checkpoint for carbs and fats.