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Over the past year or so, I have been writing my own pizza tutorial and, in the process, have written on cheeses for pizzas. Rather than trying to address your questions specifically, I have cut and pasted below some information on the more common types of pizza cheeses used and my experiences with them. I have started with the fresh mozzarella cheeses but also move on to the more common processed cheeses. In a later post, I will cover cheeses other than the common ones and also buffalo mozzarella cheeses. So, here goes.
For Neapolitan style pizzas, I recommend that fresh, whole-milk mozzarella (fior di latte or “flower of milk”), which is made of cow’s milk, be used if at all possible. The fresh mozzarella cheese is deemed by many to be preferable to the more common processed mozzarella cheese sold in ball or shredded form mainly because the fresh mozzarella cheese is considered fresher, softer, sweeter and more delicate, with a nice tang. For best results, the cheese should be reasonably firm (to permit slicing), elastic, spongy and juicy. Fresh mozzarella cheese is made by separating the curds and whey from whole milk, cooking the curds until they are elastic, stretching and pulling the curds to achieve a taffy-like texture, and then forming into balls. Usually, fresh mozzarella cheese is sold packed in water (called the governing liquid), in the form of either a single large ball or several small balls, called bocconcini or cielegine. Quite often, slightly less fresh mozzarella cheese is available, for example, from a local artisanal producer (and occasionally from a major producer), in a sealed package sold at specialty stores. The refrigerator shelf life of all of the foregoing forms of mozzarella cheese is quite short, usually only a few days once the packaging is opened.
If fresh mozzarella cheese is not available for any reason, then the more highly processed forms can be used. In some respects, the more highly processed forms of mozzarella cheese offer certain advantages over the fresh varieties. They are more stable, are drier (and not as watery on the pizza), easier to shred (especially if put into the freezer for about an hour before using), and need not be used within a matter of days. They are also more readily available and less expensive than the fresh mozzarella cheeses—although that shouldn’t be the sole reason for using them. As with any other cheese, they should be of the highest quality possible.
Processed mozzarella cheese come in many varieties, including full-fat whole milk (100%), part skim, and low-moisture/part-skim, each with its own qualities and attributes. They are often combined together on pizzas (e.g., a 50/50 blend of whole milk mozzarella cheese and part-skim mozzarella cheese) or used with other types of cheeses, of which a mozzarella cheese/provolone cheese combination (e.g., three parts mozzarella cheese to one part provolone cheese) is one of the most popular because the two cheeses have similar melting, flow and stretching characteristics (they are both stringy curd cheeses). In addition, they carry the flavors of toppings, like pepperoni, throughout the entire pizza without interfering with the flavors of other ingredients. The provolone cheese (regular or smoked) also adds a distinctive flavor.
A popular cheese combination in the St. Louis area, called “provel”, uses provolone cheese, white cheddar cheese and Swiss cheese. Other possibilities for combination with mozzarella cheese are Monterey Jack (including flavored varieties) and cheddar cheeses. Where a buttery-rich flavor and good meltability is desired, whole milk mozzarella cheese is usually used. However, unlike its lower-fat cousins, it is subject to breaking down and releasing some of its fat during baking, producing an oily appearance which may not be visually pleasing (although many love the mouthfeel of the fat). That is one of the reasons why whole milk mozzarella cheese is often combined with part-skim mozzarella cheese or provolone cheese. A very good brand of mozzarella cheese is the Grande brand, which comes in whole milk and low-moisture forms, and is available at some specialty retail stores and by mail order from some distributors to the pizza industry.
I would avoid non-fat and imitation mozzarella cheeses because they are the most inferior of all the mozzarella cheeses and there are much better choices from a quality and taste standpoint.
As between the various processed forms most commonly available to the home pizza maker, I prefer mozzarella cheese that is freshly sliced from a large block or brick of cheese, usually at the deli counters of supermarkets and food specialty stores. If a good quality deli mozzarella cheese is not available for any reason, then the packaged mozzarella balls can be used, of which there are many good, well-known brands, including Polly-O (a Kraft Foods product), Stella (which also comes in a deli style and in a coarsely shredded form), Calabro, and Dragone, just to name a few. Pre-packaged mozzarella slices are also acceptable provided they are free of chemical additives. If possible, I would avoid the very finely shredded, finely diced, or minced forms of mozzarella cheese (which usually come in plastic bags) since the cheese tends to cook too quickly and brown prematurely when used on pizzas baked at high oven temperatures. They are also highly processed with a multitude of additives to prevent caking, inhibit mold and prolong shelf life (usually measured in weeks).
Fresh mozzarella cheese and the processed varieties of mozzarella cheese discussed above should be refrigerated until ready for use, by placing the mozzarella cheeses in airtight containers (to protect flavor and freshness), ideally at a temperature between 42-52 degrees F. Processed mozzarella cheese and some of the fresh mozzarella cheeses (but not the buffalo mozzarella cheese) can also be frozen until ready for use, but this should be done quickly to prevent it from becoming crumbly. Just put the unopened ball of mozzarella cheese in a freezer bag and put into the freezer section of your refrigerator. Defrost the cheese slowly in the refrigerator section of the refrigerator about a day before you intend to use the cheese (or defrost it in the microwave on the defrost cycle for a couple of minutes, being very careful not to melt the cheese). Mozzarella cheese should not be refrozen again after having been defrosted. I usually buy mozzarella cheese in quantity and freeze whatever I do not intend to use at one time. Since mozzarella cheeses vary considerably from one producer to another, before considering freezing any particular brand of mozzarella cheese, especially fresh mozzarella cheeses, I recommend that the reader freeze a small amount of the cheese to see if it can withstand freezing and defrosting without significantly degrading its taste and texture.
Mozzarella cheeses and blends should not be used in excess on pizzas. Otherwise, the cheeses may retard the baking of the crust and result in uncooked dough. To prevent this outcome, many professional pizza makers have established guidelines relating to the amounts of cheese (including blends), by weight, that should be used on the different sizes (by diameter) of pizzas. Some typical quantities of cheese relative to the different sizes of pizzas are as follows: 10”, 5 ounces (by weight); 12”, 7.5 ounces; 14”, 10 ounces and 16”, 12.5 ounces.
For best results, it is generally recommended that meltable cheeses like mozzarella and provolone cheeses be distributed in shredded form, small pieces or chunks, large dice, or thin slices over a pizza rather than using a very finely shredded, diced or minced form. In these forms, the pieces or slices of meltable cheese will melt in “puddles” and stay soft and chewy, rather than turning brown. Alternatively, the meltable cheeses can be withheld until a couple of minutes or so before the pizza is completely baked—something I quite frequently do with Margherita pizzas and other pizzas with few toppings—or a pizza round can be baked without toppings until it sets, and then add the toppings, including the cheeses, and finish baking.