Parmigiano Reggiano

A hard, aged cow's-milk cheese produced in five provinces in northern Italy under DOP rules that have not changed in eight hundred years. Made from raw milk, no additives, aged a minimum of twelve months — the version worth buying is aged twenty-four or thirty.

The white crystals running through a well-aged wheel are tyrosine, an amino acid. They are the visible signature of the aging. They are also why a single shaving carries so much umami.