Brief
The purpose of this lab was to make our own cheese and test to see what kind of macro molecules were in our cheese. We used four different curdling agents in our experiments water, buttermilk, chymosin (fpc), and rennin (nbc). Our hope was to see the effect of the different agents of how fast the cheese would curdle, how big the curds would be, and to see what kind of macro molecules would be in out cheese. Developing a hypothesis was difficult for this project because we had no prior understanding of how the agents would work.
Procedure
- Label 4 6ml tubes with the type of curdling agent and group number
- Transfer 3 ml of milk into the 6ml tubes
- Transfer the contents of the tube containing your curdling agent into the one with milk
- Cap and flip your tube 3 times transfer to an incubator (human armpit for this test)
- Check for any curds every 5 mins
- Record how long it took to curdle
- If after 30 minutes it has not yet curdled check after an hour
- Record data on the curdling process
- On the next day check on the curds
- For each treatment weigh a paper cone
- Transfer the liquid onto the cone and wait to dry
- Weigh the dry cone with curds
- Repeat for each treatment
- Label 4 vials with the indicators used
- Mix dried cheese flakes with 2 ml of water in a small vial
- Mix until all the curds are dissolved
- To test for glucose
- Mix 2 ml of a glucose solution with 2 ml of benedict's solution in a cheese vial
- Heat for 2 minutes in boiling water
- If the mixture turns orange then your cheese has glucose
- To test for starch
- Mix 2ml of starch suspension with o.25 ml of lugol’s iodine in a cheese vial
- Gently mix
- If the mixture turns black your cheese has starch
- To test for protein
- Add 2 ml of gelatin solution into a cheese vial
- Add 1.5ml of biuret reagent and mix
- Wait 30 seconds if the color changes to purple your cheese has protein
- To test for lipids
- Add 120 μL of sudan IV solution to a cheese vial
- Carefully mix
- If the color changes to orange then your cheese contains lipids
Data
When tested for the macromolecules our cheese tested positive for glucose,starch, protein, and lipids.
Analysis
The data shows that chymosin has the fastest curdling time by far followed by rennin likely taking longer to curdle because one or two outliers in our testing. Buttermilk and water took the longest amount of time to curdle most people testing water took more than two days to curdle.
Conclusion
In the lab we found fpc to be the most effective agent to curdle milk and make cheese. The fpc was far superior to the other three curdling agents, and having an amazing curdling rate. We also discovered cheese to contain many types of macromolecules in it.
Analysis
The data shows that chymosin has the fastest curdling time by far followed by rennin likely taking longer to curdle because one or two outliers in our testing. Buttermilk and water took the longest amount of time to curdle most people testing water took more than two days to curdle.
Conclusion
In the lab we found fpc to be the most effective agent to curdle milk and make cheese. The fpc was far superior to the other three curdling agents, and having an amazing curdling rate. We also discovered cheese to contain many types of macromolecules in it.
contents
Macro molecules are a large molecule that is used to store or provide energy, the four types of macro molecules are carbohydrates, protein, lipids, and nucleic acids.
reflection
This lab was not very exciting it smelled bad and took way to long. At first making cheese seemed like fun and then we walked into class and it smelled like milk that went bad back in 2004. It took my cheese 2 days to curdle so i just got to watch people gag from the smell and drop the gloppy cheese on the floor. After the cheese had dried the lab got much better testing for different macro molecules was the highlight of this lab.