test for starch

How would you test the presence of starch in leaves?

Steps to test the presence of starch in leaves :

Step 1: A fresh leaf is taken.
Step 2: The leaf is boiled in water for few minutes to soften the cells in the leaf.
Step 3: Now, dip this leaf in iodine solution.
Step 4: The color of the leaf will changes into blue black color when iodine is added to it which shows the presence of starch in it.

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