Question

On treatment with iodine, the presence of starch is confirmed by the appearance of:

• A. Blue-black colour
• B. Blue colour
• C. Red colour
• D. Pink colour

Answer 1

The correct option is A

Blue-black colour

Iodine solution acts as an indicator to check the presence of carbohydrates or starch. Starch is a complex carbohydrate formed by the combination of many molecules of simple sugars (glucose). Blue-black colour appears when starch containing food is treated with iodine solution.