The purpose of this lab was to determine whether or not the reported amount of protein on the container is accurate. As seen on the picture of the nutrition facts, the amount of protein in the carton is 8 grams.
In order to this, we used concentrated acetic acid to denature the proteins. Denaturing of proteins allows for the curdling of milk into a substance that can be filtered out. This substance is the protein in the milk. After filtering the solution, we would then mass it and that is the experimental value of protein in the skim milk.
In the picture above, our male model, Than, is measuring out 15 milliliters of skim milk. 
We then added 30 mL of acetic acid to the milk, stirred it in, and let it sit for about 5 minutes to denature the proteins within.
Once the acetic acid denatured the proteins, they were separated from the rest of the milk and we could filter out the whey portion of the milk, leaving behind 0.72 grams of solid protein curds based on the following data we retrieved.
Data:
Mass of Total Milk (g): 15.12
Mass of Filter and Protein (g): 2.44
Mass of Filter (g): 1.72
Mass of Protein (g): .72
Expected Mass of Protein (g): .51
Percent Yield (%): 4.76%
Percent Error (%): 41%
The data above shows that we ended up getting results that seem to say that we filtered more protein than is advertised, but this is unlikely, as the company would probably prefer to say that have as much protein as possible. The most likely cause of our positive percent error was that we were not able to filter out all the filtrate successfully, so some of it would have remained in our filtered protein, thereby increasing its calculated mass. This makes our results rather invalid. What may have caused this was that we ran out of time to fully filter out the whey so it remained with the protein. We expected the calculated amount of protein to be less than what the milk carton reported, but our results said otherwise.
Therefore, we cannot draw a conclusion as to whether the company accurately reports the amount of protein.
