food tests

• What is benedicts used to test for?


  Sugars
• Whta is biuret used to test for?


  proteins
• What is iodine used to test for?

  Starch
• What is Sudan 111 used to test for?


  lipids (fats)
• If sugar present it will turn...

  Orange/red colour
• If protein present it will turn...


  Purple
• If starch present it will turn...

  Blue/black
• If lipids present it will turn...

  Milky white/cloudy
• Steps of food test practical:

  1. Get peice of food and break it up using water and pestle
  2. Put crushed food into beaker with distilled water
  3. Stir with glass rod until some peices of the food dissolve
  4. Filter out the solution with a funnel and filter paper to get rid of the solid bits of the food
  5. Solution that is left over will be put into a test tube and used for the food test
  6. Add a few drops of biuret/benedict/iodine/suden 3
  7. Heat test tube in a water bath for approx 10 mins at around 75 degrees