Question

Test for Starch:
Preparation of dilute iodine solution

Take a test tube or a cup and add few drops of iodine crystals to it. Then dilute it with water till it becomes light yellow/brown.

Take a sample of food item in the test tube. Add a few drops of dilute iodine solution to the sample.

Observe the change in colour. What do you find?

If the substance turns dark-blue or black it contains starch. Try with ripen banana and curry banana.

Science lab activity​

Answer 1

Answer:

Saliva contains starch breaking enzyme that is amylase while potato contains starch in it. Therefore when iodine is added in both tube the color of tube B changes to dark blue which indicates the presence of starch while no reaction takes place in tube A which means there is no starch.