Lesson 1.4: Investigation: Testing for Nutrients

How do scientists determine if a food contains a particular nutrient?  They perform tests for particular nutrients.  You are going to learn about the tests and what chemicals are used for particular nutrients.  Proteins are an important nutrient in your diet.  What is the test for protein?  Watch the following video clip to see what the test is and how it is done.  Note: The video may take some time to load depending on your internet connection speed.  When the video is loaded the play arrow will turn from grey to black.  If the video will not play, right click on the page and select the refresh option.  The video should then work. 

Now answer the following questions about the protein test.

Question 1. What chemical is used to test for protein in a food?

Question 2. Explain how the test is performed.

Question 3. What happens in the test if there is protein in a food?

Question 4. What colour indicates the most protein?

Question 5. What happens if there is no protein in the tested food?

 

Check your answers by selecting the + sign.

 

Add a small amount of Biuret solution to the food ( the food should be in solution ) and mix.
If there is protein in the food, the solution will turn pink, violet, or purple.
Purple indicates the most protein.
If there is no protein in the tested food, there is no colour change.

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. What chemical is used to test for protein in a food?

Biuret solution. 

Question 2. Explain how the test is performed.

Add a small amount of Biuret solution to the food ( the food should be in solution ) and mix.

Question 3. What happens in the test if there is protein in a food?

If there is protein in the food, the solution will turn pink, violet, or purple. 

Question 4. What colour indicates the most protein?

Purple indicates the most protein.

Question 5. What happens if there is no protein in the tested food?

If there is no protein in the tested food, there is no colour change.

 


Click on the page forward to continue Lesson 1 ...