Aging Parmesan: How Long Does It Take?

Parmigiano-Reggiano, or Parmesan, is a hard, dry cheese made from skimmed or partially skimmed cow's milk. It is typically aged for at least 12 months, but the longer it's aged, the more its character, flavour, appearance and texture change. The minimum maturation time for Parmigiano-Reggiano is 12 months, after which each wheel of cheese is inspected and, if approved, fire-branded to become 'real' Parmigiano-Reggiano. However, the cheese is usually aged for much longer – some for over 100 months.

Parmigiano Reggiano must be aged for at least 12 months

Parmigiano Reggiano, or "the king of cheese", is a protected designation of origin (PDO) cheese, meaning it must be produced in a specific region and follow strict guidelines. As such, it must be aged for at least 12 months to be considered authentic.

After 12 months of ageing on wooden shelves, each wheel of Parmigiano Reggiano is inspected and fire-branded. At this stage, the cheese is still soft and young, and has yet to develop the unique flavours and perfumes for which it is famous. However, it can be called Parmigiano Reggiano, and it is often aged for much longer – up to and beyond 36 months.

The longer the ageing process, the more the cheese's texture and flavour will change. After 18 months, the number of visible white crystals increases, and the cheese becomes noticeably crumbly and grainier. These characteristics become even more pronounced as the cheese continues to age, and the flavour profile evolves to include umami notes like nuttiness and meat stock.

By the time it reaches 30 months, aged Parmigiano Reggiano is considered "very old". The cheese becomes particularly dry, crumbly and grainy, with a powerful and decisive aroma. Notes of spice and dried fruit come to the fore, and the cheese is perfect for grating or eating with honey or balsamic vinegar. At this stage, it is also highly digestible and suitable for babies and those who are lactose intolerant.

While it is rare, it is possible to find Parmigiano Reggiano that has been aged for 60, 72, or even 90 months. These extremely well-aged cheeses have a wide essence and a deep, unique flavour. They are best enjoyed on their own, with a sweet wine like Marsala or Passito to balance out their hardness.

The cheese is tested and fire-branded after 12 months

Parmigiano Reggiano, or Parmesan, is a protected designation of origin (PDO) cheese. This means it must be produced in a specific region around the Italian provinces of Parma and Reggio Emilia. It also means that it must be aged for at least 12 months before it can be called Parmigiano Reggiano. After 12 months, each wheel of cheese is tested and fire-branded. This involves assessing the external appearance of the wheel and its internal texture through a percussion hammer test. If the cheese passes the selection examination, it is branded with an oval shape containing the wording "Consorzio Tutela Parmigiano-Reggiano" and the year of production.

At 12 months, Parmesan is still considered young and is described as "new" by experts. The cheese is soft, and the flavours and perfumes that make it famous worldwide are not yet fully developed. However, the cheese does have a strong lactic base, giving it a taste of milk, yoghurt, or butter. There may also be vegetal notes such as grass, boiled vegetables, flowers, or fruit.

After the initial 12-month ageing process, Parmesan is usually aged further, often for years. The flavour and texture of the cheese will continue to change and develop over time. From 12 to 18 months, Parmigiano-Reggiano still exhibits some of its youthfulness, with milk, yoghurt, and fresh fruit flavours. By 24 months, the cheese becomes crumbly and grainier, and the number of visible white crystals increases. The flavour also becomes more complex, with the addition of umami notes like nuttiness and meat stock.

As the cheese reaches 36 months or older, notes of spices become more prominent in both the aroma and flavour. The cheese becomes drier, even more crumbly, and gains an intense flavour. At this stage, milk enzymes digest casein, making it suitable for lactose-intolerant individuals and babies. Parmigiano Reggiano can even be aged for much longer—some cheeses are aged for 60, 72, or even 90 months. These rare, aged cheeses have a wide essence and a unique deep flavour that can be balanced with a sweet wine like Marsala or Passito.

Parmigiano Reggiano can be aged for over 100 months

Parmigiano Reggiano, or "the king of cheese" as some call it, is a Protected Designation of Origin (PDO) cheese, meaning it must adhere to strict rules and guidelines. For a cheese to be deemed Parmigiano Reggiano, it must be aged for at least 12 months on wooden shelves. After this period, each wheel of cheese is inspected by the Parmigiano Reggiano Consortium, who will approve the cheese if it passes their quality inspection. At this point, the cheese is still soft and young, without the unique flavours and perfumes that make it famous.

Parmigiano Reggiano can be aged for much longer than 12 months, and the character of the cheese will continue to change as it matures. From 12 to 18 months, Parmigiano Reggiano still exhibits some of its youthfulness, with flavours often described as "milk, yogurt, and fresh fruit". By 24 months, the changes are clear, not just in flavour, but in appearance and texture. The cheese becomes crumblier and grainier, and the number of visible white crystals increases.

As the cheese reaches 36 months or older, notes of spices become more prominent in both the aroma and flavour. Wheels can eventually be over-aged, turning completely gritty, but this is unlikely to be an issue for consumers unless you are ageing whole wheels of Parmigiano Reggiano at home. If you happen to come across a 50-month Parmigiano Reggiano, you can expect an intensely crystallised treat.

Aged Parmigiano Reggiano can also be found at 60, 72, and even 90 months. These cheeses are difficult and rare to find, as they must have the perfect shape and aging, but the reward is a wide essence and a unique deep flavour.

The cheese is usually aged for at least two years

Parmigiano-Reggiano, or Parmesan, is a hard, dry cheese made from skimmed or partially skimmed cow's milk. It has a hard, pale-golden rind and a straw-coloured interior with a rich, sharp flavour. The cheese is produced in Italy, specifically in the provinces of Parma, Reggio Emilia, Mantua, Modena, and Bologna.

Parmigiano-Reggiano is typically aged for at least two years. This lengthy aging process results in the cheese's complex flavour and extremely granular texture. The minimum maturation time for Parmigiano-Reggiano is 12 months, after which the cheese is inspected and, if approved, receives the official Parmigiano-Reggiano designation. However, the cheese is usually aged further, and its character and flavour profile will continue to evolve with time.

At 12 months, Parmigiano-Reggiano is considered young or "new" by experts. The cheese is still tender, with less predominant aromas. The flavour is described as having an accentuated lactic base, tasting of milk, yogurt, or butter, with possible vegetal notes such as grass, boiled vegetables, flowers, or fruit. From 12 to 18 months, the cheese still exhibits some youthfulness, with "milk, yogurt, and fresh fruit" flavours.

By 24 months, the changes in appearance, texture, and flavour become more noticeable. The number of visible white crystals increases, and the cheese becomes crumbly and grainier. The cheese has reached an optimum degree of ripeness and has a perfect balance of sweet and salty flavours. It is versatile and can be used in various gastronomic preparations, including being grated over first courses.

After 30 months, Parmigiano-Reggiano is considered "very old". The cheese becomes particularly dry, crumbly, and grainy, with an intense and decisive aroma. Notes of spices and dried fruit dominate the flavour profile. At this stage, the cheese is highly digestible and suitable even for lactose-intolerant individuals and young children. It is perfect for grating or enjoying with honey or balsamic vinegar.

While it is rare, Parmigiano-Reggiano can be aged even longer, up to 60, 72, or even 90 months. These extremely aged cheeses have a wide essence and a unique deep flavour. They are typically enjoyed alone, paired with a sweet wine like Marsala or Passito, to balance their hardness.

Parmigiano Reggiano is aged on wooden shelves

The wooden shelves in the ageing rooms are stacked 24 cheeses high and 90 cheeses long, or 2,160 total wheels per aisle. Each cheese is placed on a shelf and is then cleaned and turned every seven days.

At 12 months, the Consorzio del Formaggio Parmigiano Reggiano inspects every wheel. A master grader taps each wheel to identify undesirable cracks and voids within the wheel. Wheels that pass the test are then heat-branded on the rind with the Consorzio's logo.

The ageing process can continue for up to 36 months, and sometimes even longer. The longer the cheese is aged, the drier and crumblier it becomes, with an increasingly intense flavour.

The ageing process also makes Parmigiano Reggiano suitable for those who are lactose intolerant. After 30 months, milk enzymes digest casein, making the cheese safe for those with lactose intolerance and for babies.

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