Quality over Quantity
Ikejime (活け締め) or Ikijime (活き締め) is a humane method of killing fish to maintain the quality of its meat. The technique originated in Japan, but is now in widespread use. It involves the insertion of a spike quickly and directly into the hindbrain, usually located slightly behind and above the eye, thereby causing immediate brain death. When spiked correctly, the fish fins flare and the fish relaxes, immediately ceasing all motion. Destroying the brain and the spinal cord of the fish will prevent reflex action from happening; such muscle movements would otherwise consume adenosine triphosphate (ATP) in the muscle, and as a result produce lactic acid and ammonia, making the fish sour, soggy and less tasteful. Furthermore, the blood contained in the fish flesh retracts to the gut cavity, which produces a better coloured and flavoured fillet, and prolongs shelf life. This method is considered to be the fastest and most humane method of killing fish. Ikejime-killed fish is sought-after by restaurants as it also allows the fish to develop more umami when aged.