Different Types Of Proteins

Different Types Of Proteins

Proteins are needed by our body for muscle building and repairing worn-out tissues. Our muscles, organs, and even blood are made up of mostly proteins. If we do not eat proteins, our body will not be able to repair damaged cells, or build new ones. Proteins in our diet come from both animal and plant sources. Meat, fish, egg, and milk are some animal sources of proteins. Pulses, soyabeans, grams, and nuts are some plant sources of proteins.

Activity

Aim: To test the presence of proteins in a food item.
Materials needed: Food sample, copper sulphate solution, sodium hydroxide, test tube, and Bunsen burner.
Method:

1. 1. Crush a small amount of the food sample (if solid) and put in the test tube.
   2. Add some water to the test tube and shake it.
   3. Next, heat the test tube for about 1 minute.
   4. After the test tube has cooled down, add two drops each of copper sulphate solution and sodium hydroxide to it.

Observation: The food sample turns purple or violet.
Conclusion: Change in colour of the food sample to purple or violet confirms the presence of starch.