Food tests

• What is the purpose of the video?

  To explain different food tests
• Which food tests are covered in the video?

  Benedict's, iodine, Buret, Sudan 3 tests
• What is the first step in preparing a food sample?

  Break it up using a mortar and pestle
• What should you do after crushing the food sample?

  Add it to a beaker with distilled water
• What is the purpose of filtering the solution?

  To remove solid bits of food
• What are sugars in carbohydrates classified into?

  Reducing sugars and non-reducing sugars
• What does the Benedict's test detect?

  Reducing sugars
• How do you perform the Benedict's test?

  Add 5 cm³ of sample and 10 drops of Benedict's solution
• What temperature should the water bath be set to for the Benedict's test?

  75 degrees Celsius
• What color indicates the presence of reducing sugars in the Benedict's test?

  Green, yellow, or brick red
• What is starch classified as?

  A type of carbohydrate
• How do you perform the iodine test for starch?

  Add a few drops of iodine solution to the sample
• What color change indicates the presence of starch in the iodine test?

  From browny orange to blue black
• What does the Buret test detect?

  Proteins
• How much sample is needed for the Buret test?

  2 cm³
• What color change indicates the presence of proteins in the Buret test?

  From blue to pink or purple
• What is the Sudan 3 test used for?

  To test for lipids
• How do you perform the Sudan 3 test?

  Add 3 drops of Sudan 3 to the sample
• What indicates the presence of lipids in the Sudan 3 test?

  A bright red layer at the top
• What is the emulsion test used for?

  To test for lipids
• How do you perform the emulsion test?

  Add 2 cm³ of ethanol and shake vigorously
• What indicates the presence of lipids in the emulsion test?

  A cloudy white color
• What are the steps to prepare a food sample for testing?

  1. Break up the food using a mortar and pestle
  2. Add to a beaker with distilled water
  3. Stir until dissolved
  4. Filter the solution to remove solids
• What are the key differences between the Benedict's test and the iodine test?

  • Benedict's test detects reducing sugars
  • Iodine test detects starch
  • Benedict's test changes color based on sugar concentration
  • Iodine test changes from browny orange to blue black
• What are the key differences between the Buret test and the Sudan 3 test?

  • Buret test detects proteins
  • Sudan 3 test detects lipids
  • Buret test changes from blue to pink/purple
  • Sudan 3 test shows a bright red layer
• What are the common steps in food testing procedures?

  1. Prepare food sample
  2. Add appropriate reagent
  3. Observe color change
  4. Interpret results based on color
• What are the safety precautions for the Benedict's test?

  • Use a test tube holder
  • Point the tube away from yourself
  • Handle hot equipment carefully