【Reading】いけじめ

【English Name】Ikejime / draining blood from a live fish to keep it fresh

Ikejime is a groundbreaking processing method that the Japanese fishing industry devised to address the challenge of preserving freshness. A freshly caught fish is swiftly brain-killed and its blood is drained from the body—this sequence of operations is the key to maintaining flesh quality and flavor over an extended period.

Why It Works
When a fish thrashes about, its ATP (adenosine triphosphate) is rapidly depleted, lowering the efficiency of its conversion into inosinic acid, the source of umami. Ikejime cuts off this depletion and serves to draw out the maximum amount of umami. In addition, it simultaneously prevents the deterioration of the flesh caused by internal bleeding and the loss of flavor caused by the buildup of lactic acid. Because the onset of rigor mortis is delayed, the rate of spoilage also slows, and removing the blood reduces the breeding ground for microbes.

Techniques by Fish Species
For flounder and red sea bream, after piercing the vital point behind the eye with a hand gaff in a single thrust to sever consciousness, the area near the medulla oblongata and the base of the tail are cut open to bleed the fish. When handling tuna, a spiral needle is used to destroy the nerve from the medulla oblongata, then the process moves on to bleeding.

History and Spread Overseas
It originated in the very beginning of the Edo period. Since then, fishermen across Japan have honed the technique in the field and passed it down across generations. By the 2010s, riding the wave of the global Japanese food boom and the spread of information via the internet, it spread overseas as well. In the English-speaking world, recognition has grown to the point that the term "ikejime" is understood, and in Britain and France there are notable cases of it being used as a differentiating brand.

It is also sometimes written as "ikijime" or "ike-jime." Processing through natural death or by freezing in ice water is distinguished separately as "nojime."