Parmesan

Parmigiano Reggiano is aged 12 months at the least and commonly 24 or 36, and histamine rises with ageing - EFSA ranked the fermented categories but could not put numbers on them, so read that as a direction rather than a rate, with a well-aged wheel as the reference point at the top of this axis. Its specification forbids additives and selected cultures, so nothing slows the bacteria down. A grating is a small portion, and that is the only thing in its favour.

Parmigiano Reggiano is aged 12 months at the least and commonly 24 or 36, and tyramine tracks ageing closely - which puts a well-aged wheel at the top of this axis with mature cheddar. The specification forbids additives, selected cultures and silage feed entirely, so nothing interrupts the bacteria: the ageing is the whole story. The white crystals in an old piece are tyrosine, the amino acid they turn into tyramine.

Parmigiano Reggiano is one of the cheeses measured with no detectable lactose AND no detectable galactose - the zero here is a measurement, not an assumption. Twelve months is its minimum ageing and most wheels go well beyond: the whey left first and the cultures spent the rest. The white crystals in an old piece are tyrosine, not milk sugar.