Decay rate changes

• To investigate the effects of temperature on decay, measure the pH change of fresh milk in the presence of the enzyme lipase
• • Make a solution of milk and phenolphthalein indicator.

  
  

  • Add sodium carbonate which will cause the solution to become alkaline and therefore appear pink

  
  

  • Place the tube in a water bath at a specific temperature. Add the lipase enzyme and begin stopwatch.

  
  

  • Time how long it takes for the pink colour to disappear (i.e. when the pH has decreased).

  
  

  • Repeat this at different temperatures to see at which temperature the pink colour disappears the quickest, indicating the quickest decomposition.

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