Lipid Test:
Do not use palm nut oil, because it is too red! Put some vegetable oil into a small, clear bottle. Add a cap-full of iodine solution, then close the bottle and shake vigorously. A red ring should form. After addition to a sample, the iodine will move the less dense fat layer that separates above the water. As the iodine is concentrated in this thin layer, a red ring forms at the top of the sample.