Using an iodine solution, you can test for the presence of starch. When starch is present, the iodine changes from brown to blue-black or purple.
Buiret solution is a blue liquid that changes to purple when proteins are present
The Sudan IV test for the presence of lipids: Sudan IV (C24H20N4O) is a red, fat-soluble dye used for staining lipids, triglycerides and lipoproteins.
Is what i found. Hope it helps you
