Whether oozing off of a slice of pizza or layered in a lasagna, mozzarella cheese has become a household favorite, and probably something we eat nearly once a week. But fresh mozzarella is quite different from the shredded cheese. It is a sliceable curd cheese originating in Italy and traditionally made from the milk of water buffalo (not North American buffalo or bison as many mistakenly think), and its flavor is highly prized.
The Italian Mediterranean buffalo breed is believed to have been introduced to Italy in Roman times or later by Barbarian invasions of Italy. Since these animals are herded in only a few countries, primarily Italy and Bulgaria, most mozzarella is now made from cow's milk; in fact, much of the mozzarella cheese we find in our local supermarket is made from cow's milk. If you are shopping for fresh traditional mozzarella, you might look for the label "mozzarella di bufala."
Water Buffalo Milk vs. Cow's Milk
Water buffalo milk is very high in fat and casein, making it not easily digestible in its raw form. It is not consumed as a beverage as cow milk is, but is used for making mozzarella, burrata, ricotta di bufala, yogurt, and similar products. The milk of the Italian Mediterranean buffalo is three times more expensive than cow's milk and is costly to ship, so expect a correspondingly high price tag for imported buffalo mozzarella.
Water buffalo milk is also much more nutritious than cow's milk with higher concentrations of calcium, protein, and iron, as well as being lower in cholesterol. Mozzarella contains 40 to 45 percent fat. Lower-fat versions are made with part skimmed milk.
In Italy, if you want cow's milk mozzarella, you ask for mozzarella fior di latte, which may be made with pasteurized or unpasteurized cow's milk. In the U.S., this would be the same as the common mozzarella seen in the cheese section of the grocery store.
Sheep's milk mozzarella can be found in some areas of Italy, including Sardinia, Abruzzo, and Lazio. Goat's milk mozzarella is made by some small producers.
How Fresh Mozzarella Is Made
No matter which type of milk is used, fresh mozzarella is made in the same manner. Mozzarella cheese is not aged like most cheeses and is actually best when eaten within hours of its making. The process of making mozzarella is called pasta filata. The milk is incubated with a whey starter containing thermophilic bacteria. Then rennet is added to form the curds. The curds are heated in water or whey until they form strings (hence the term "string cheese") and become elastic in texture. The curds are stretched, kneaded until smooth, and then formed into round balls to make fresh mozzarella cheese.
If you would like to make your own, it is easy to make homemade mozzarella cheese. You need only rennet, citric acid, milk, and water. You can find rennet and citric acid in specialty markets and health food stores that may cater to home cheesemakers, or online. In 30 minutes you can have fresh mozzarella to enjoy and impress your family or guests.
Storage and Use of Fresh Mozzarella
If you buy or make fresh mozzarella, you should keep it in liquid until you are ready to use it. Packaged mozzarella usually includes some liquid. Keep mozzarella refrigerated; because of the high moisture content, it does not keep as long as harder cheeses. Low-moisture mozzarella will keep longer.
You are probably familiar with shredded mozzarella layered on pizza and baked Italian dishes, but mozzarella can be used in a variety of recipes, including salads, meats, poultry, seafood, and vegetables. Caprese salad with fresh mozzarella, tomato, basil, olive oil, and capers is a delightful traditional use of fresh mozzarella.