CP: Testing foods

Question 1

What does iodine test for?

What does the colour change indicate (darker)?

Answer 1

Starch
If the substance is darker (black-blue), there is a lot of starch.
If the substance turns yellow, there isn’t a lot of starch.

Question 2

What does Biuret test for?

What do the colour changes indicate?

Answer 2

Biurets tests for protein.

A darker violet colour indicates there is a lot of protein.

Question 3

What does ethanol test for?

What does the change indicate?

Answer 3

Ethanol tests for fats (lipids).

A white emulsion indicates there is fat.

Question 4

What does Benedict’s solution test for?

What do the colour changes indicate?

Answer 4

Benedict’s Solution tests for sugars.
If the solution turns orange or yellow, there is sugar.
Blue-green or yellow-green is negative.