food tests

• food tests for starch: iodine solution turns blue/black
• emulsion test - tests for fats and lipids

  add ethanol to a food sample , shake vigorously then add water solution will turn cloudy if there's lipids
• Burette test - tests for protien

  add potassium hydroxide to food sample, when shaken solution may turn lilac / purple
• benedict's test- tests for reducing sugars

  add food sample in a test tube and put in a 75 water bath then ad 10 drops of benedict's solution , if there are sugars present, solution may turn green yellow or red
• what are the limitations of calorimitry?

  • incomplete burning - can be solved by relighting the food sample until it no longer lights up
  • heat energy is lost to the surroundings - calculation becomes inaccurate