Squid ink is stirred into squid salt-cure. That is the entire difference between this and the ordinary version, and it turns the whole jar black. Strips of squid are cut fine and left to mature with the ink. Nothing goes into the jar that did not come out of the same animal.

The colour is alarming and the taste is not, which catches people out. Squid ink carries a good deal of glutamic acid and taurine, so the result is deeper and rounder than the usual red-brown shiokara, and less sharply fishy. People who avoid salt-cured squid on principle sometimes find this one acceptable.

There is a surviving document recording that the lord of Kaga presented it to the shogunal household during the journeys to and from Edo that the domains were required to make. It travelled as a product of Toyama, which was the branch domain, and it was received well enough to be written down.

Now it sits beside a drink, or on top of rice, and it is eaten all year round rather than seasonally. Households here keep a jar of it in the refrigerator as a matter of course. Something once sent up to a shogun is now behind a kitchen door, and the only part of it that has not changed is the colour.