What Is Parmesan Cheese? The King of Italian Cheese

Parmesan is one of those words that gets thrown around loosely. Sprinkle some on pasta. Shake it from a green can. But authentic Parmesan — Parmigiano-Reggiano — is a DOP-protected cheese with strict production rules, a mandatory aging process, and a flavor profile that domestic imitations cannot replicate. Understanding the difference changes how you use it.

What Is Parmigiano-Reggiano?

Parmigiano-Reggiano is a hard, granular cheese made from raw cow's milk in specific provinces of Italy: Parma, Reggio Emilia, Modena, Bologna (west of the Reno River), and Mantua (east of the Po River). It carries DOP (Denominazione di Origine Protetta) status, meaning every wheel must be produced, aged, and inspected within that geographic zone. The milk comes from cows fed on local grass and hay — no silage allowed. Each wheel weighs approximately 80 pounds and requires about 131 gallons of milk to produce. The cheese has been made using essentially the same process since the 13th century.

How Is Parmesan Aged?

The aging process defines Parmesan. After the wheels are formed and brined in salt water for 20 to 25 days, they enter aging rooms where they rest on wooden shelves. At 12 months, the cheese is mild and slightly elastic. At 24 months, it develops a crumbly, crystalline texture with sharp, nutty flavors. At 36 months and beyond, the flavor intensifies into a complex profile with notes of butterscotch, dried fruit, and roasted nuts. Those crunchy white specks in aged Parmesan are tyrosine crystals — amino acid clusters that form during extended aging. They are a sign of quality, not a defect.

What Is the Difference Between Domestic Parmesan and Parmigiano-Reggiano?

Domestic Parmesan — the kind sold pre-grated in plastic containers — is a different product. In the United States, "Parmesan" is a generic term with no aging requirement, no geographic restriction, and no production standard. Domestic Parmesan is typically aged 10 months or less, made from pasteurized milk, and produced in factories. The flavor is milder, the texture softer, and the umami profile significantly weaker. Pre-grated versions often contain cellulose (wood pulp) as an anti-caking agent. Imported Parmigiano-Reggiano costs more — $18 to $25 per pound versus $6 to $10 for domestic — but a small amount delivers far more flavor because the aging concentrates everything.

Is Parmesan Cheese Halal?

Traditional Parmigiano-Reggiano uses animal rennet — an enzyme derived from the stomach lining of calves. This makes authentic Italian Parmesan non-halal unless the rennet comes from halal-slaughtered animals, which is rare for DOP-certified wheels. However, many domestic Parmesan producers use microbial rennet or vegetable-based rennet, which is halal-compliant. At Forni, we source cheeses made with microbial rennet so our entire menu remains 100% halal. When we shave Parmesan over a finished pizza or salad, you can eat it without question.

Parmesan is not a topping you pile on. It is a finishing ingredient. A few shavings on a hot pizza add umami depth that makes every other flavor on the pie taste more like itself.

How Is Parmesan Used on Pizza?

Parmesan is a finishing cheese, not a melting cheese. Unlike mozzarella, which goes on before baking, Parmesan is shaved or grated over the pizza after it comes out of the oven. The residual heat softens the shavings slightly without melting them into a pool. This preserves the granular texture and delivers concentrated flavor in every bite. At Forni, we use it on our Bianca pizza — shaved over arugula and white sauce — and as an optional finish on any pie. A little goes a long way because aged cheese packs exponentially more flavor per gram than young cheese.

Parmesan at Forni

Every cheese at Forni is halal — including our Parmesan. We use it as a finishing touch, shaved fresh over pizzas, salads, and paninis. The 800-degree oven does the heavy lifting on flavor, and the Parmesan adds a layer of savory depth that rounds out the whole plate. Visit us at 5800 Seminary Rd in Falls Church to see how aged cheese and real fire work together.

Want to learn about the other cheeses we use? Read our complete guide to pizza cheeses →