Emphasise the need for enzymes as well as the effect of pH or temperature changes on the digestion of a food.
Two processes have been chosen:
1. The action of amylase (saliva enzyme) on starch.
2. The action of pancreatin (pancreatic juice enzyme) on egg white.

Composition (for 15 pairs of students):

• Amylase 0.4g
  
• Starch 0.3g
  
• Pancreatin 24g
  
• 31 tubes of 50ml
  
• 50ml of lugol and 2 discs of soda
  
• 2 sterile calibrated droppers
  
• 2 5ml pipettes
  Technical and educational instructions available on our website.
  
  No. of pairs of students: 15
  Preparation time: none
  Necessary material: Water bath or oven at 37° C, demineralised water, egg white.