Say Mozzarella

By John Brody, Contributing Editor

Historically speaking, mozzarella cheese originated in the Naples-Salerno region of southern Italy in the 17^th century, where it is known as mozzarella di bufala. This unique fresh cheese is made from water buffalo milk. It is an excellent melting cheese with a soft, creamy texture and a rich, clean dairy taste. The production of this cheese remained regional in Italy due mainly to the limited supply of water buffalo milk and the short shelf life of the cheese.

When pizza started to become popular in the United States in the 1950s, a more robust type of mozzarella was needed to cope with the increasing demand. This new cheese had to have a longer shelf life and needed to be firmer and easier to shred. What evolved were two slightly different types of cheese, one with high fat content and one with a lower fat content. The high-fat cheese is now universally called low-moisture whole-milk (LMWM) mozzarella, and the low-fat version is called low-moisture part-skim (LMPS) mozzarella. Both of these cheeses have a Standard of Identity in Title 21, Part 133 of the Code of Federal Regulations: LMWM mozzarella must have a moisture content between 45% and 52% and a fat in dry basis (FDB) of greater than 45%; LMPS mozzarella must have similar moisture, but the FDB has to be between 30% and 45%.

Almost all mozzarella contains the same four ingredients:  milk, cheese cultures, enzyme and salt. When setting out to make a particular version of mozzarella, a cheesemaker has to balance the ratio of fat to protein in the milk in order to end up with the correct composition. Normally, there is more fat in milk than is required, so in order to come up with the correct ratio, three different methods are employed. One method involves separateion, or removing a pre-determined portion of fat from the milk. Another method involves leaving the fat in the milk and achieving the correct ratio by adding additional protein. To do this, condensed skim milk is added to the cheese milk. The third method employed is similar to the second method except skim milk powder instead of condensed skim is added directly to the milk. Most cheese plants are set up to do all three methods, and the method chosen primarily depends on which is most economical at the time. Be aware that the three methods can produce slightly different properties in the cheese when it is cooked on pizza.

Mozzarella cheese also goes through a process called pasta filata. This involves taking the cheese curd prior to salting and immersing it in hot water [167 F°]. The curd heats up to 134 F° and becomes molten and free-flowing. In this condition, it is pulled and stretched under the water. This process causes the protein in the curd mass to align, which in turn gives the resultant cheese its stringy, chicken breast-like texture. It is also the reason why mozzarella stretches when cooked.

Following the pasta filata process, the hot cheese is molded and placed in a brine solution where it cools down and takes up salt. After brining, the salt is concentrated on the outside of the block and requires about 7 to10 days to become evenly distributed throughout the cheese. Because of this, it is important not to use mozzarella that is too fresh (less than 10 days old), as the results could be inconsistent.

From a pizza-making point of view, traditionally made LMPS and LMWM mozzarella performs best when the age of the cheese is between 14 days and less than 60 days of age. After this time, the uncooked cheese will start to soften and will be difficult to cut and shred, and the cooked cheese will start to break down and have a tendency to flow excessively and suffer from weak body and lack of stretch.

Browning is another issue that affects mozzarella. In general, people on the East Coast do not like to see any browning on cooked cheese, whereas people in the Midwest and West coast like to see a reasonable amount of golden-colored browning on their pizza. While browning is a complicated issue involving both Malliard reactions and lactose breakdown and utilization, some degree of control can be exerted at the cheese plant by the careful selection of cheese cultures.

As well as having exceptional cooked properties, mozzarella cheese should have a mild dairy flavor. Unlike many other cheeses, the flavor of mozzarella will not increase significantly as it ages. By shredding and then blending other cheeses with mozzarella, additional flavors can be introduced. The most common cheeses used for blending with mozzarella are parmesan, provolone, romano, muenster and cheddar.

John Brody is technology principalnatural cheese, Sargento Foods Inc., Plymouth, WI. He earned his B.S. in dairy and food science from University College Cork in the Republic of Ireland. He was winner of the European Cheddar Cheese Championship in 1988, and has used his technical expertise about cheesemaking in both Irish and U.S. firms for more than 30 years.

Photo: Sargento Foods, Inc.