Test for Sugar & Starch

Test for Reducing Sugar Using Fehling’s Solution:

To a little quantity of the solution of glucose in a test tube, add few drops of Fehling’s solution. A yellow precipitate is formed, which turns brick red on warming.

Note that a non-reducing sugar like sucrose does not form precipitate with Fehling’s nor Benedict’s solution. 

Test for Starch

To a little solution of starch in a test tube, add a few drops of iodine solution. A black blue colouration is formed which disappears on heating and reappears on cooling