Cheese Lab Report
Effects of Temperature on the Formation of Cheese Curds
This lab was performed in order to find what temperature the enzyme chymosin is most effective at forming cheese curds. An enzyme is a protein that acts as a catalyst to speed up biological reactions in cells. They work by lowering the activation energy and help to orient the molecules correctly. Chymosin was originally taken from the stomachs of calves, and was called rennet, and then purified to make rennin. Eventually to catch up with demand, biotechnology was used to clone rennin and mass produce it, becoming chymosin.
We tested the efficiency of chymosin at 20°C, 30°C, 40°C, 50°C, and 95°C. I tested it at 50°C and 95°C. My hypothesis was that chymosin would be most effective at 40°C because that is approximately the temperature of a calf’s stomach and nature tends to be very efficient.
Materials:
5 specific temperature water baths corresponding to the temperatures above
5 test tubes
25 ml whole milk
Chymosin
1 Timer
5 Coffee filters
1 graduated cylinder
1 electronic scale
Procedure: Set up 5 different water baths at 20°C, 30°C, 40°C, 50°C, and 95°C. In a group label each 5 test tubes with the group name. Find the mass of 1 coffee filter, this will be important for later. Each person will be responsible for one temperature, and measure 5 ml of whole milk into a test tube. Then take each test tube and place it in the appropriate water bath, and wait 3 minutes for the milk temperature to adjust. Once each test tube has adjusted, add 10 drops of chymosin and start the timer. Every 5 minutes check the test tube for coagulation, and compare to the control which has 10 drops of water rather than chymosin. Record this on your data table. After 40 minutes, remove each test tube from the bath and filter out the cheese curds using a coffee filter. Using a scale, find the mass of the cheese curds, and remember to subtract the mass of the coffee filter. Record it in the data table
This lab was performed in order to find what temperature the enzyme chymosin is most effective at forming cheese curds. An enzyme is a protein that acts as a catalyst to speed up biological reactions in cells. They work by lowering the activation energy and help to orient the molecules correctly. Chymosin was originally taken from the stomachs of calves, and was called rennet, and then purified to make rennin. Eventually to catch up with demand, biotechnology was used to clone rennin and mass produce it, becoming chymosin.
We tested the efficiency of chymosin at 20°C, 30°C, 40°C, 50°C, and 95°C. I tested it at 50°C and 95°C. My hypothesis was that chymosin would be most effective at 40°C because that is approximately the temperature of a calf’s stomach and nature tends to be very efficient.
Materials:
5 specific temperature water baths corresponding to the temperatures above
5 test tubes
25 ml whole milk
Chymosin
1 Timer
5 Coffee filters
1 graduated cylinder
1 electronic scale
Procedure: Set up 5 different water baths at 20°C, 30°C, 40°C, 50°C, and 95°C. In a group label each 5 test tubes with the group name. Find the mass of 1 coffee filter, this will be important for later. Each person will be responsible for one temperature, and measure 5 ml of whole milk into a test tube. Then take each test tube and place it in the appropriate water bath, and wait 3 minutes for the milk temperature to adjust. Once each test tube has adjusted, add 10 drops of chymosin and start the timer. Every 5 minutes check the test tube for coagulation, and compare to the control which has 10 drops of water rather than chymosin. Record this on your data table. After 40 minutes, remove each test tube from the bath and filter out the cheese curds using a coffee filter. Using a scale, find the mass of the cheese curds, and remember to subtract the mass of the coffee filter. Record it in the data table