Requirements (Instruments, Chemicals & Other) :

1. Protein powder
   
2. Analytical Balance
   
3. Conical flask
   
4. Petri-dish
   
5. Whatman filter paper
   
6. Convective hot air oven
   
7. Shaker
   
8. Buffer solution
   
9. Measuring cylinder
   
10. Distilled water
    
    

Procedure :

1. Weigh 10g protein powder (S) in five different conical flasks.
   
2. Pour 100 ml buffer solutions of pH 3.0, 4.0, 4.5, 6 and 8 in the five different proteins containing conical flask and marked as the A, B, C, D and E respectively.
   
3. Shake the flasks at 200 rpm for 10 min.
   
4. Filter the solution of each flask using Whatman filter paper.
   
5. Transfer filter paper containing insoluble matter inside the pre-weight petridish.
   
6. Put the Petridish in the oven and dry the content at 105°C for 3 hrs.
   
7. Record the weight of petridish after 3 hrs of drying.
   
8. Weigh Whatman filter paper and record the weight.
   
9. Calculate using formula:
   

10. Draw curve solubility (%) Vs pH.