Week 2 Lab Group C Data: Cheesemaking

Our lab group was originally designated with making mozzarella. While the end result was ultimately much different than what we had intended, the following data may still be useful in determining processes and dynamics that are integral to successful cheesemaking, by showcasing an instance when it was largely unsuccessful.

Weight Milk + Carton (g)	2870
Weight Carton (g)	918
Weight Milk (g)	1952

Weight Curd + Colander (g)	563
Weight Colander (g)	217
Weight Curd (g)	346

Weight Cheese + Sieve (g)	255
Weight Sieve (g)	25
Weight Cheese (g)	230

We began the lab by starting the inside down fire. While we waited for the fire to catch more thoroughly, we weighed the milk. We first weighed the milk in the carton, then poured the milk into the cast iron pot and weighed the milk carton, then subtracted the two to get the weight of the milk in isolation (Table 2). we then squeezed lemons to create the appropriate amount of lemon juice for the water/juice mixture (~2.5 lemons) and poured that into the milk. We then placed the milk/water/lemon mixture on the fire to heat. The pattern of heating is shown in Figure 1, with accompanying data in Table 1. While described in our lab write-ups in more detail, essentially what occurred was that the milk heated much more quickly than we expected, it continued to raise in temperature after we removed it from the fire upon the mixture reaching 90º at minute 2.33, and it took a long time (~20 mins) to dip back to ~90º. Then, after we added the rennet, the mixture repeatedly fluctuated between ~80º and ~100º; our attempts to stabilize it on the fire ended in overheating the mixture to greater than 100º. This is likely the reason for our low results of curd and cheese weights (Tables 3 and 4). Other observations from the lab included the following: it was 44º F and sunny with 14mph, gusting up to 22mph winds during the lab; we were working from 1pm-5pm; we used a metal fire pit and an upside down fire building method; and the metal fire bin was 650º F before we added the milk and 780º after we removed the milk. Our thermometer also seemed to be “lagging” slightly; during the process after we added the rennet, thermometer would continue to quickly drop in temperature for ~15 seconds after we put the mixture on the fire, then quickly jump up ~15-20º, at which point we would hurriedly remove it from the fire. This process of attempting to maintain ~90ºF while using a seemingly fickle thermometer resulted in us overheating the rennet mixture to ~105º F, at which point we simply left the mixture alone, hoping to still make some sort of cheese. We ultimately did make cheese, but the amount was much smaller than other groups and its consistency was much “wetter” than others; there was still some whey sitting atop the cheese after a day of drying.