Barfoed's test


  • This test distinguishes a reducing monosaccharide from a reducing disaccharide.


  • Monosaccharides are oxidized under acidic conditions.
  • Monosaccharides take a shorter time, while disaccharides take a longer time to react.
  • Brick red color obtained in this test is due to the formation of cuprous oxide.


  • To 3 mL of Barfoed’s reagent in a tube add 0.5 mL of test solution.
  • Heat the tube and observe the time taken to form the brick red color.
Last modified: Wednesday, 23 March 2011, 7:01 AM