Mozzarella

Mozzarella is made by ripening cow's or buffalo curd until it reaches a precise acidity, then plunging it into water at around 90C and working it until it turns glossy and stretches without tearing. Portions are pinched off by hand, a gesture called mozzatura, and it is where the name comes from. There is no ageing at any point.

Two Italian products share the name. Fiordilatte is cow's milk: sweeter, drier, cleaner. Mozzarella di Bufala Campana DOP is made from the milk of the Italian Mediterranean water buffalo, which carries roughly twice the fat and far more protein than cow's milk. It gives a whiter, wetter, tangier cheese with a faintly mineral edge.

The third product is the one most Americans mean by the word: low-moisture mozzarella, a briefly aged, saltier, firmer block engineered to melt and brown in an oven. It is a good cheese doing a different job. Sold shredded or in a plastic-wrapped brick, it is not what you put in a caprese, and fresh Italian mozzarella is not what you shred over a pepperoni pizza.

Fresh mozzarella tastes of warm milk with a light lactic tang, faintly salty, more sweet than savoury. The pleasure is as much textural as anything: a slight resistance, then a squeak, then the milky liquid that comes out when you bite.

Buffalo mozzarella pushes every dial further. It is tangier, richer, wetter, with a grassy, almost mineral finish and a mouth-coating creaminess that cow's milk cannot reach. Fiordilatte is rounder and gentler, and better when something else on the plate is meant to be the star.

Low-moisture mozzarella tastes mildly salty and slightly cooked, with almost no tang. Cold, it is bland and rubbery. Hot, it does the thing nothing else does as well: stretches, browns and stays put.

Take it out of the fridge half an hour before serving, in its liquid. Cold mozzarella tastes of nothing. If you are in a hurry, sit the unopened tub in warm water for five minutes.

Raw, it needs very little: ripe tomato, basil, good olive oil, flaky salt. Anchovies, capers or a slice of prosciutto work because they bring salt and acid, not more fat.

For anything baked, the enemy is water. Tear or slice it, spread it on a rack or in a colander and let it drain for 30 to 60 minutes, longer for buffalo. On a Neapolitan pizza, that draining is the difference between a cheese that melts and a soup. On a New York-style pizza, use low-moisture instead and stop fighting the ingredient.

Day-old mozzarella has one perfect use: mozzarella in carrozza. Sandwich it between two slices of white bread, dip in milk, then flour, then beaten egg, and shallow fry until the outside is gold and the inside is molten.

Fresh mozzarella is a short life product and the date on the tub is the only authority on it. Keep it refrigerated in its own liquid, sealed, and never pour that liquid away to save space: it is what stops the ball drying. Once open the clock speeds up, and Italian shops sell it to be eaten that day or the next. If it has left its brine, sitting it in lightly salted water or a little milk slows the surface drying, though flavour leaches into whatever it sits in.

What changes is measurable. The outer skin toughens and turns rubbery, the interior loses the wet layered structure and compacts, acidity climbs so the taste sharpens, and the liquid around it goes from clear whey to cloudy. Buffalo balls move through all this faster than cow milk. Freezing is possible but not free: ice crystals cut the fibrous curd, and it thaws grainy, releasing water, which rules out raw use and leaves it only for baking. Low moisture mozzarella in a block is the opposite case, keeping several weeks sealed and drying gradually at the cut face once opened.

In a non-Italian shop the word mozzarella covers two unrelated things. Fresh mozzarella sits in its own cloudy liquid, in a tub or sealed pouch, soft enough to tear. Low moisture mozzarella is the shrink wrapped block or the bag of shreds, drier and built for pizza. A good fresh ball is porcelain white with a thin, faintly glossy skin, yields under a finger and springs back, and tears into wet layers rather than crumbling. Cut it and a few drops of milky liquid run out.

The second confusion is buffalo against cow. Mozzarella di Bufala Campana DOP is 100 percent water buffalo milk, brilliant chalk white, softer and more lactic; the pack carries the consortium seal and that exact wording. Anything labelled simply fresh mozzarella, or fior di latte, is cow milk: ivory rather than white, firmer, milder. Both are legitimate, but only one carries the DOP price, roughly $12 to $20 for a 250 gram ball in the US against $5 to $8 for domestic cow milk. A ball priced like the cow version but sold as buffalo deserves a second look at the label.

In the US, DOP buffalo mozzarella is flown in weekly and sold by Eataly, Murray's Cheese, DiPalo's in New York and shippers such as Gustiamo: expect $9 to $16 for a 250g ball, and check for the consortium mark with the buffalo head and a lot number rather than the word 'buffalo' on a label. For fresh cow's-milk mozzarella, Lioni, Calabro, BelGioioso and Di Stefano are all reliable and sold nationally at $6 to $12 per pound. Low-moisture blocks run $4 to $7 per pound in any supermarket.

In the UK, Waitrose, Ocado, Sainsbury's and M&S all carry DOP bufala at roughly £2.50 to £4 for 125g, which works out to £20 to £30 per kilo; Natoora and Italian importers supply restaurant-grade product, and La Latteria in London makes fresh mozzarella in the city. Cow's-milk fresh mozzarella is around £12 to £18 per kilo.

Wherever you buy it, look at the production date rather than the expiry date, and reject anything sitting in cloudy, stringy liquid.

The Sele plain south of Salerno (Battipaglia, Capaccio, Paestum) is the single best place on earth to eat buffalo mozzarella, because the dairies sell over the counter from six in the morning and many have the herd on site. A mozzarella two hours old is a different food from a refrigerated one, and it is worth building a morning around.

The other production heartland is the Volturno plain north of Naples, around Aversa and Mondragone. In Naples itself the good delis take delivery twice a day, and the classic pizzerias will tell you whether the pizza is made with fiordilatte or bufala.

For cow's-milk mozzarella, climb to Agerola in the Monti Lattari above the Amalfi Coast, or go to Gioia del Colle on the Murgia plateau in Puglia, which has its own DOP and almost no tourism.