Sample Hypothesis:If the mystery food is tofu, then it will react with the reagent that indicates the presence of a protein because tofu is primarily protein. Which reagent is used to test for protein?

Hypothesis:

If the mystery food is tofu, then it will react with the reactant that indicates the presence of a protein because tofu is primarily protein.

Purpose:

To explore the presence of nutrients in food using a laboratory experiment and deductive reasoning.

Summary:

The mystery food was a lipid because it reacted to the Sudan Red solution. The mystery food didn't react to any other food other than lipids. This leads us to believe that a person who ate a salad with some dressing, spilled some on the table. Her salad dressing was made up of fats, which are lipids.

Biuret solution. Biuret solution is used to identify the presence of protein. Biuret reagent is a blue solution that, when it reacts with protein, will change color to pink-purple.

The correct answer is biuret reagent.

Explanation:

Tofu is coagulated and pressed soya milk which is rich in protein content used by athletes and gym trainers.

To test the protein content in the food material - tofu reagent used is - Biuret reagent which is a blue colored aqueous solution prepared by the mixing of potassium sodium tartrate with sodium hydroxide and cupric sulfate. This reagent in the presence of peptide bonds of proteins changes its color from blue to pink-purple. This change in color shows the presence of proteins.

Thus, biuret reagent is the correct answer.