Food Tests

• Before doing Food Tests. You must always

  
  

  1. Grind the food with distilled water with a mortar and pestle

  
  

  2. Place Grinded food in beaker with more distilled water.

  
  

  3. Filter the solution
• TEST FOR STARCH

  
  

  - Place 2cm3 of food solution test tube

  - Add Iodine(brown/orange) to it

  - If present = Blue-Black
• TEST FOR SUGAR

  
  

  - Place 2cm3 of food solution test tube

  
  

  - Add 10 drop of Benedict (blue) to it

  
  

  - Place test tube in hot water bath

  
  

  - Leave for 5 minutes.

  
  

  - If present = Green,Yellow, Brick-red (from small to big sugar smount)
• TEST FOR PROTEIN

  
  

  - Place 2cm3 of food solution test tube

  - Add Biuret(blue) to it

  - If present = Purple/lilac
• TEST FOR SUDAN III LIPIDS

  
  

  - Place 5cm3 of food solution in test tube

  
  

  - Pipette Sudan III solution to it

  
  

  - Shake test tube gently

  
  

  - If present = a bright layer of red on top.
• FOOD TESTS (PRESENT)

  
  

  Starch = Iodine - Brown to Blue-Black

  Protein= Biuret - Blue to Purple/lilac

  Lipids = Sudan III - Two layers, top red

  Sugar = Benedict - Blue to Brick-Red
• In the Lipids SUDAN III test, if Lipids aren't present one white layer will form.