For wood-fired, kinda soggy-in-the-middle, true Neapolitan pizzas, a high-moisture, freshly made mozzarella (preferably from water buffalo milk!) is key. But for the vast majority of pizza styles in the U.S.—our beloved New York style, crispy Greek style, bar pies, New Haven apizza, even Chicago deep dish pies—low-moisture aged mozzarella is the cheese of choice.
So what's the difference anyhow? All mozzarella starts with fresh cheese curds made by adding rennet to lightly fermented cow or water buffalo milk. The curds are then allowed to rest and sour a bit more until a desirable flavor is achieved, whereupon they're placed in hot water until the firm protein structure begins to loosen up a bit. What follows is a slow, gentle kneading process that you'd like to imagine is performed by practiced and seductive Italian hands, but in reality, the vast majority of the stuff you get here is probably kneaded in a decidedly un-sexy manner by a cold, calculating, lifeless machine. No matter. Either way, this stretching action works much in the same way that kneading bread dough does: it causes proteins to link together, creating the long, stretchy strands that mozzarella is known for.
Stretched cheeses like this, which include provolone, cacciocavallo, and scamorza among others, are collectively known as pasta filata, which translates literally to "pulled paste" or "spun paste." I prefer the Italian nomenclature.
To make low-moisture mozzarella, the fresh mozzarella is then allowed to further sour, then carefully dried in a controlled environment. There are a few reasons why most pizzerias choose low-moisture mozz: First off, it's got a much longer shelf life. Fresh mozzarella is best the day it's made, and rapidly deteriorates, developing off-flavors within the first few days. Low-moisture mozzarella can last for weeks under refrigeration, meaning easy transportation and the ability to buy in bigger bulk—an all around cheaper option. According to the FDA, low moisture mozzarella must have a moisture content in the 45 to 52% range, while regular mozzarella can be as much as 60% water—sometimes even higher if you buy it from a specialty shop that still spins by hand.
As for flavor, low-moisture mozzarella is saltier and denser. Depending on how long it's aged and at the temperature it's held at, various bacteria can help it to acquire some of the tangy characteristics of aged cheeses like a provolone or cheddar. For pure meltability, nothing beats low-moisture mozzarella. While fresh mozz exudes water as it melts and becomes more soupy than melty, The best low-moisture mozzarella should stretch and stretch, yet still remain dry enough that the pizza crust remains intact.
There's a pretty staggering array of mozzarellas available in most supermarkets. Our question is, which brand is best? And if we can't recommend a specific brand, are there any general suggestions that will help lead you towards a better, meltier, tastier choice?
The Contenders
For our tasting, we gathered 11 of the most commonly available brands across the country (in alphabetical order):
- Boar's Head
- Calabro
- Capiello
- Horizon Organic
- Kraft
- Organic Valley
- Polly-O
- Sargento
- Sorrento
- Trader Joe's
- Whole Foods 365
When available, we chose whole milk blocks of cheese, though some brands were only available in part-skim or pre-shredded form. In order to evaluate the cheeses, we tasted all of them both in raw form, and melted onto French bread pizza (a childhood throwback flavor greatly appreciated by even the most snobbish of NY and Neapolitan pizza snobs (of which there are none in this office, I swear)).
By and large, we were unimpressed by the unmelted stuff, which has very little flavor aside from a mild milkiness. The most noticeable difference between the raw cheeses was between the pre-shredded and the block cheese. Pre-shredded mozzarella comes coated with a desiccating powder (either cellulose, potato, or cornstarch), designed to prevent the individual shreds from clumping together. This works, except it gives the cheese an unpleasantly gritty mouthfeel when eaten raw. That said, the only people who eat raw mozzarella are crazies and wackos, so who cares?
The other major thing we noticed in our raw tasting was that a couple brands—notably Kraft and Whole Foods 365—didn't taste like mozzarella They were perfectly fine as a Provolone or even a Cheddar, but they were distinctly nutty and tangy, and not at all mozz-y.
Meltability
With mozzarella, meltability is priority numero uno. We want our cheese to spread out in a rich, gooey blanket over out pizza. Premature crust formation is a major fault. When you cut a pie into individual slices, the mozzarella should ooze cleanly around the knife. If the knife is able to pull it away in sheets or the mozzarella separates from the pie underneath, that's a major detractor. We want every bite of pizza to have melty cheese that stretches away from the remaining slice in thin strands. Biting into the cheese and having the whole thing come away like a giant scab is, well, gross.
Meltability is what mozzarella is all about—if it don't got the stretch, then tasters will kvetch. If it's nice and elastic, then it's all fantastic. If it ain't gooey, then I say phooey. If it don't extend, then we can't recommend. If you can't draw it out, it's not... Ok, sick of this game. You get the picture.
The overriding factor in how well the cheeses melted was their fat content. Whole milk mozzarella, like the one pictured above on the right, spread into an even layer that stayed moist and stretchy even when slightly browned. Skim or part-skim mozzarella, on the other hand, formed the unattractive sheets that you see on the left when even lightly browned. In fact, fat content showed the highest correlation between well-ranked cheese and poor. Every single part-skim mozzarella scored below every other full-fat mozzarella.
Also important was pre-shredded versus block. Because of the added starch, pre-shredded mozzarella tended to both brown faster, and form the unattractive crust you see in the pie above. That said, there were a couple of whole block cheeses that ended up ranking below the shredded versions.
What was most surprising of all was that aside from the very bottom ranking cheeses—the Whole Food's 365 brand for skim, and surprisingly, the Calabro for whole milk (their ricotta is the best major commercial brand you can get)—to a large degree, the brand made very little difference. Amongst the whole milk cheeses, we'd happily take any of the options we tasted. Similarly, amongst the skims, there were no real superstars or low-liers.
The real question we had was that given that whole milk mozzarella really only has a gram or two of extra fat per serving versus part-skim mozzarella, why would anyone ever choose the latter?
Beats me.
The Winners
First Place: Polly-O
Second Place: Trader Joe's
Third Place: Capiello