The production of Parmigiano Reggiano, the king of Italian cheeses, is one of long tradition and strict regulation. The cheese must be aged a minimum of 12 months before being inspected and deemed worthy of the DOP (Denominazione di Origine Protetta) stamp. One thing that must be true of all Parmigiano Reggiano is that it is made from 100% raw cows milk. So how does a pure cows milk cheese become lactose free? Through a maturation process dating back several centuries.
During the early stages of maturation, bacteria turns the lactose into lactic acid. By the end of the minimum 12 months of aging, the amount of lactose in the cheese barely registers above 0. Despite its name, lactic acid is actually safe for those with a lactose intolerance.
There are a number of other hard, aged cheeses that are also lactose free, including Parmigiano Reggiano’s close cousin, Grana Padano. Just be aware. A cheese simply named “Parmesan” may not be aged enough to be lactose free. When purchasing a wedge of Parmigiano Reggiano, always buy one with a bit of the rind with the “Parmigiano Reggiano” stamp, otherwise it may not be the real thing.