food tests

Cards (8)

  • what test is used to test for sugars:
    • Benedict's test
  • Once you add the Benedict's solution, you must heat it in a water bath for 5 minutes at 75°C
  • what test is used to test for starch:
    • iodine
  • if starch is present the colour will change from orange to black
  • what test is used to test for proteins:
    • biurets solution
  • if protein is present the colour change is:
    • Blue to lilac / purple
  • what reagent is used to test for lipids:
    • Sudan III stain
  • Sudan III test for lipids:
    • Place 5cm3 of your food sample in a test tube.
    • Add 3 drops of Sudan III stain solution. 
    • Gently shake.
    • If a red layer separates out on top, then lipid was present.