3. Write test for detecting the presence of starch.

Take a piece of the food item. Put 2-3 drops of dilute iodine solution on it. If the colour of the food item becomes blue-black, then it indicates the presence of starch in the food item. (i) Food + Iodine — Blue-black colour (starch present) (ii) Food + Iodine — No blue-black colour (no starch present)