Parmesan cheese – officially known as Parmigiano-Reggiano, a name that under Italian law can only be applied to products made in the designated provinces – is a hard, granular cheese manufactured from unpasteurised cows’ milk. The designated provinces of Italy are Parma, Reggio-Emilia, the area of Bologna west of the River Reno, Modena, and the part of Mantua south of the River Po. In addition to the Italian law, European law also prevents anyone else using the translation “Parmesan”, but this only applies within the European Union.
The cows have to be fed only grass or hay.
The process begins with the milk collected at the evening milking. This is left to stand overnight in shallow tanks which allows the cream to separate. This cold, partly skimmed milk is then mixed with the warm, whole milk collected at the morning milking. The mixture is then rapidly cooled in copper-lined vats. Starter whey is added and the temperature raised to 33-35°C (91-95°F). Calf rennet is added and milk is left to curdle for 10-12 minutes. The curd is then broken up mechanically into small pieces about the size of rice grains. The temperature is then raised to a precise 55°C (131°F) and the mixture is left to settle for around 45-60 minutes. The compacted curds are collected up in muslin and then divided into two and placed in molds, each vat being enough to create two cheeses each. Traditionally, the leftover whey was fed to pigs that were destined to become Parma ham.
Each cheese goes into stainless steel rounds that are tightened up with a spring buckle so that the cheese keeps its shape. After a couple of days the buckle is released and a plastic belt with the official logos and production details is put round it. These gradually transfer to the rind of the cheese and the wheel is then put in a brine bath so that it can absorb salt for 20-25 days.
After brining, the cheese wheels are transferred to special aging rooms for 12 months. The shelves in some production places can be as high as 24 cheeses and 90 long, giving a total of 2,160 cheeses per aisle. Each cheese is turned, and both cheese and shelf cleaned every seven days.
After 12 months, the wheels are inspected by regional officials and tested by a master grader. Those that pass the test are given the official logo and those that don’t have their rinds marked with lines or crosses to warn consumers they are not buying the top quality product, although more recently the practice of stripping off the rind has been preferred.
The cheese has a long history and has always been highly prized. The English diarist, Samuel Pepys, recorded that during the Great Fire of London in 1666 he buried his “Parmazan” cheese together with his wine in the garden to preserve them.
Parmesan cheese is most commonly grated over pasta dishes or stirred into soups and risottos, or shaved over salads. It can also be eaten on its own, and responds well to roasting.
Outside the European Union, there are producers who make a Parmesan-style of cheese and call it Parmesan.