In cheap mortadella, Zivieri adds, its distinctive piggy smell is added chemically, ‘like a perfume’. I watch as the mixed meat and fat is squeezed into its casing, then deftly wrapped in twine.

The biggest difference between the two is that mortadella has cubes of fat separated from the pork, which are visible in its slices. It's also often spiced. Bologna is much more uniform looking ...