Experiment No. 18
Question: How can you discover if food contains protein?
Experiments: To test for protein.
You will need:
Five test tubes,
test tube rack,
four food samples – tuna, cheese, milk, pâté and Biuret reagent.
1. We placed some Biuret
solution into one test tube.
2. We placed four different food samples into four different test tubes.
3. We then placed Biuret solution into the pipette (enough for ten-twelve drops)
4. We then added approximately 10 drops to each food sample, in each test tube.
5. Then we waited and observed the Biuret reagent.
6. We recorded the results.
|Observations:||The Biuret reagent turned from blue to a purple colour.||The Biuret reagent turned from blue to a purple colour.||The Biuret reagent turned from blue to a light purple colour.|
1. If the Biuret reagent
stays blue then there is no protein present.
2. If the Biuret reagent changes to a purple type colour then protein is present.
Sixth Class Experiments