Food tests

• Use the Benedict's Test to Test for Sugars


  1. Place sample in test tube

  2. Heat the sample

  3. Observe color change
• Use Iodine Solution to Test for Starch


  1. Add iodine solution to sample

  2. Observe color change
• Use the Biuret Test to Test for Proteins


  1. Add sample to test tube

  2. Add biuret solution

  3. Observe color change
• Use the Sudan III Test to Test for Lipids


  1. Add sample to test tube

  2. Add Sudan III stain

  3. Observe color separation
• The chemical used to test for the presence of starch is iodine solution
• What temperature should be used for Benedict’s test?

  75
• Which food test detects lipids

  Sudan III Tests
• Which food test detects sugar

  Benedict’s test
• Which food test detects starch

  Iodine solution
• Which food test detects proteins

  Biurets test
• What colour is a positive sugar test

  Green , yellow or brick-red
• What colour is a positive starch test

  Black or blue-black
• What colour is a positive protein test

  Purple
• What does a positive lipids test look like

  A second layer that is bright red
• What colour is a negative sugar test

  Blue
• What colour is a negative starch test

  Browny-orange
• What colour is a negative protein test

  blue
• What does a negative lipids test look like?

  no observable change