Evidence of Protein and Starch in Organic Materials

The purpose of this scientific experiment is to test for organic macromolecules such as Proteins and Starch in different organic materials used in everyday life, by using a reagent specifically designed to indicate the presence or the lack of these organic macromolecules.

Hypothesis:
Di Water doesn’t contain Protein
Milk solution contain Protein
50% egg white solution contain Protein
1% sucrose solution doesn’t contain Protein

Materials and Methods:
A test tube rack 4 to 5 test tubes Transfer pipets
Protective glasses 3 pieces of paper bag Deionized water
Milk solution 50% egg white solution 1% sucrose solution
Biuret Reagent Wax pencil Gloves

To test these different materials for protein, Biuret reagent will be used and test deionized water, milk solution, 50% egg white solution, and 1% sucrose solution. First, all 4 test tubes has to be labeled with a wax pencil to indicate the material within, and placed …show more content…
The color of Biuret reagent is blue. When Biuret is added to the substance and that mixture remains blue in color, it will indicate a negative result for protein. If Biuret is mixed with the substance and the mixture is purple or pinkish purple, it is an indication of a positive result, and the presence of protein.
After adding and mixing the reagent to the 4 test tubes the results are as follows:
Test tube 1 which contains deionized water turned blue after mixing Biuret reagent.
Test tube 2 which contains milk solution is pinkish purple.
Test tube 3 which contains a 50% egg white solution is purple.
Test tube 4 which contains a 1% sucrose is light blue.