Mozzarella is a type of cheese originating from the Southern tip of Italy. This cheese was first made with Buffalo’s milk and is still considered a delicacy. Today, Mozzarella is made with cow’s milk around the world (Zonis, 2006). Mozzarella’s name is derived from the Italian verb, “mozzare,” meaning”to cut off”. This name was given to the cheese because of the action of cutting the curd into smaller pieces. Mozzarella is normally a white cheese that is very moist. The trick to making Mozzarella, is not in complex ingredients, but the complexity of heating and cooling the cheese several times throughout the process (New England Cheesemaking Suppy, 2011).
Mozzarella cheese begins with adding citric acid to water. The citric acid causes the milk to instantly curdle. Without citric acid, the curd would not be able to be stretched to achieve the milky-smooth texture of Mozzarella. To aid in stretching the milk, the milk proteins casein’s must be broken down. The citric acid is the first attempt to break down the proteins into amino acids. Since the citric acid is slow, rennet will come in and finish the job (Maranowski, 2008). The acid will not add flavor or color to the cheese. Citric acid is the acid found in citric fruits like lemons and lime. It has a white appearance and salt like texture. The taste is sour, hence why lemons are sour!
 |
| Citric Acid |
 |
| Citric Acid in Water |
The next step is to add the rennet. The word “Rennet” was derived from the German word “rennen” which means to “run-away” or “coagulate”. In the kitchen, we use rennet, but the biologically correct term is chymosin. Ending in “sin” indicates rennet may be a enzyme... (Fankhauser, 2009).
That’s correct!
Rennet is a natural occurring enzyme found in the stomach of a young cow, goat, or sheep. It causes curdling of the milk producing the curds and whey. Rennet is also known to coagulate the milk in the terms that the milk yields chunks (curds) and liquid (whey) (Pav, 2010). The mechanism by which rennet works is destabilizing the casein protein in the milk, encouraging the proteins to join together, forming a gel. The rennet targets the kappa casein, rendering it inactive. Since kappa casein prevents the alpha and beta from bonding to one another, once kappa casein in inactive, the alpha and beta caseins can be precipitated by the calcium in the milk. The act of precipitation causes casein proteins to become solid or the curds (McGee, 56).
 |
| Thistle Plant for vegetable rennet |
For our Mozzarella cheese we used the Rennet tablets by Junket. These tablets are made vegetable or plant materials and will still curdle milk. This is for vegetarians and vegans (McGee, 57). The thistle flower is used for rennet instead of a young calf’s stomach lining. Vegetable rennet is intended to work as well as animal base rennet.
 |
| Rennet and Water |
 |
| Curds forming |
The next steps in cheese making is the delicate balance between heating and cooling. The citric acid was added to the milk and heated to 90 degrees. The milk mixture began to thicken at this point and chunks formed.The high temperature aids the acid in its act of destabilizing the proteins. The milk mixture was removed from the heat (cooling) and the rennet was added at this point to pick up where the acid left off. The milk mixture continued to thicken. The rennet was gently stirred in to ensure even distribution, but slowly to prevent disturbing the curd formation. The cheese was left to sit for 40 minutes. During this time the curds where forming and a chunky, white layer formed on top of the whey, which was a yellowish color. After 40 minutes, the curds were cut into small chunks, hence the name Mozzarella. The curds and whey were again heated to 105 degrees. The second heating killed bacteria and encouraged flavor in the cheese. Heating also promotes the whey separating form the curds (McGee, 61). Again, the cheese was removed from the heat and cooled. With a metal colander, the curds where strained to remove excess whey. This was repeated twice to collect more curds (more curds=more cheese). At this time, the curds were white chunks. To achieve the smooth cheese, the curds where reheated to 130 degrees. Measuring the temperature was difficult at this time because the cheese was not liquid. The temperature was carefully watched to prevent the cheese from getting too hot. The final step in cheese making is kneading and stretching the cheese till the Mozzarella is smooth and creamy. Our cheese did not get to the stage of creamy. We microwaved the curds twice and continued to knead the cheese. Other students mentioned microwaving the curds 4-5 times for the creamy texture. The Mozzarella was very moist and did not have a strong flavor as expected. The texture was soft and gummy like. We did not add salt, which we should have for flavor and preservation (McGee, 61). Overall, the cheese was a success.
 |
| Curds forming |
 |
| Cutting the Curds |
 |
| After 40 minutes |
 |
| The Whey |
 |
| The Curds |
 |
| Before the final heating |
 |
| Stretching the Cheese |
 |
| End Product |
In other cheeses, they are aged for days to years. During this time the cheese is exposed to bacteria and mold to intensify the flavor of the cheese. The growth is regulated by the humidity and temperature of the storage facility. This process results from the breakdown of casein proteins and the milk fat. The cheese may be wrapped in wax, natural rinds, or wraps. The key to the environment is it must be kept dry! Today, prepared bacterial cultures are prepared to give consistent results in cheese. For example, blue cheese is from a prepared bacterial culture (McGee, 61).
Fankhauser, D. (2009, November 23). Rennet for making cheese. Retrieved from http://biology.clc.uc.edu/fankhauser/cheese/rennet/rennet.html
Maranowski, M. M. (2008, December 1). How far can you stretcha the mozzarella: The science of making cheese!. Retrieved from http://www.sciencebuddies.org/science-fair-projects/project_ideas/FoodSci_p041.shtml
McGee, A. (2005). On food and cooking, the science and lore of the kitchen. Scribner Book Company.
New England Cheesemaking Supply. (2011). Ricki's 30 minute mozzarella . Retrieved from http://www.cheesemaking.com/howtomakemozzarellacheese.html
Pav. (2010, July 19). Understanding coagulants. Retrieved from http://www.wacheese.com/index.php?option=com_content&view=article&id=73:understanding-coagulants&catid=47:starter-cultures&Itemid=67
Zonis, S. (2006, May). Get to know marvelous mozzarella. The Nibble, Retrieved from http://www.thenibble.com/reviews/main/cheese/cheese2/whey/2006-05.asp
No comments:
Post a Comment