Testing for proteins

• What materials are provided for the protein testing experiment?

  • Food to be tested
  • A pestle and mortar
  • A glass rod
  • Distilled water
  • A 250 cm beaker
  • Filter funnel and filter paper
• What are the steps to prepare the food sample for testing?

  1. Grind the food using a pestle and mortar.
  2. Add distilled water to the ground food.
  3. Filter the mixture using a filter funnel and filter paper.
• How do you test the food sample for proteins?

  Add Biuret solution to the filtered solution
• What indicates the presence of proteins in the food sample?

  A color change to purple
• What are the key components of the protein testing procedure?

  1. Prepare food sample.
  2. Add 1cm of sodium hydroxide solution
  3. Add a few drops of copper sulphate solution
  4. Mix thoroughly and leave for 3 mins
  5. Record results.
• What is the color of the solution if no proteins are present?

  Remains blue
• What are the potential hazards in the experiment?

  • Chemical spills
  • Broken glassware
  • Inhalation of fumes