Polysaccharides such as starch and amylose can be differentiated with the help of the iodine test. Here, a few drops of 0.01 M iodine in 0.12 M KI are added to a 1% solution of the carbohydrate in question. The immediate formation of a vivid blue colour indicates amylose. On the other hand, the formation of Blueblack colouration due to the polyiodide complex indicates the presence of starch. in order to produce the tri-iodide anion, elemental iodine can be dissolved in aqueous potassium iodide. A blue-black colour is produced by the resulting complex. It can be noted that the intensity of the colour decreases when the temperature is increased and when water-miscible organic solvents (such as ethanol) are present.