Ike Jime

Grand Cayman Fishing Charters

Ike Jime – The Most Humane Way to Kill a Fish and Preserve the Meat

Originated in Japan, Ike jime (活け締め) or Iki jime (活き締め) is a humane method of killing fish. It also preserves and maintains the quality of its meat for human consumption. The principle is simple: The less trauma a fish suffers before, during, and after slaughter, the better the meat quality. As a fish struggles and stresses, it produces lactic acid and cortisol, which lowers meat quality. Disrupting the brain and spinal cord swiftly stops the stress signals and associated chemicals. Experience the best Grand Cayman fishing with Ike Jime, a time-honored technique for preserving the freshness and quality of your catch. Book your adventure today!

The basic steps:

– Boat the fish
– Remove the hook (angler safety)
– Use a brain spike to quickly kill the fish – ike jime
– Bleed the fish – Exsanguination
– Destroy the spinal cord with a “circuit breaker” wire – shinkei jime
– Place fish in an ice slurry bath.

Quick action will produce the best results from Iki jime. Once the fish is on the deck, thrust a brain spike into the fish’s hindbrain, usually located slightly behind and above the eye, thereby causing immediate brain death. The hindbrain runs the anatomic functions that are essential to survival, like respiration and motor activity. When spiked correctly, the fish fins flare, and the fish relaxes, immediately ceasing all motion. If the fish is too active to spike, club the fish to stun it before spiking the brain.

Yellowfin Tuna hind brain
The hindbrain is located behind and above the yellowfin’s eye
Brain spike to yellowfins hind brain
A spike inserted into the fishes hindbrain will cause immediate

Now it’s time to bleed (exsanguinate) the fish.

 

There are many techniques to do this. The primary method is to cut the gills or the artery behind the pectoral fin.

How to Bleed a yellowfin tuna
To bleed the fish make a cut by the gills, behind the pectoral fin and where the body meets the tail

Next, destroy the spinal cord. Even though the brain spike killed the fish, its nervous system is still functioning. This functioning causes muscle movements that produce lactic acid and ammonia. These compounds decay the flesh, hurt the texture, flavor, and shelf life. To stop this, destroy the spinal cord (shinkei jime) with a thick gauge wire, sometimes called a “circuit breaker.” There are a few methods and tools to do this. Some will go through the hole from the brain spike, and others will make a slice just before the tail and go into the spinal cord from that direction.

Perform Ike Jime on a yellowfin tuna
from the head -A heavy gauge wire is inserted into the spinal cord.
Wire- Circuit breaker inserted into the spinal canal stops all body function
from the tail- A heavy gauge wire is inserted to destroy the spinal cord

The final step is placing a fish in an ice slurry bath. The best way is to use two parts ice to 1 part seawater. This ice bath will allow the remaining blood to exit and quickly cool the fish. It is vital to keep the fish flat to prevent the loins from becoming misshaped.
This method is considered to be the fastest and most humane method of killing a fish. Ike jime killed fish are sought after by restaurants and, when aged, develop a more umami flavor.

ike jime kits
ike shinkei jime kit (18 guage)
Circuit Breakers are available in various lengths and gauges.

 

Brain locations for select species

Dispatch Method:

Mahi

mahi mahi hind brain location

The eating qualities of these fish is greatly improved if they are killed immediately by iki jime or a firm knock to the head before placing them in an ice slurry after bleeding. Mahi mahi can be very energetic and therefore hard to handle. A firm knock on the head may be easier to implement to stun the fish first before attempting iki jime.

Yellowfin Tuna

yellowfin tuna hind brain location

Dispatch Method:

The eating qualities of yellowfin tuna can be greatly improved if they are killed immediately by iki jime before placing them in an ice slurry after bleeding. A firm knock on the head may be required to stun larger fish first before attempting iki jime.

Wahoo

wahoo hind brain location

Dispatch Method:

Beware of the sharp teeth of wahoo when handling them, even after they are dead. The eating qualities of these fish can be greatly improved if they are killed immediately by iki jime or a firm knock to the head before placing them in an ice slurry after bleeding. A firm knock on the head may be safer to implement to stun wahoo first before attempting iki jime. Experience thrilling Grand Cayman wahoo fishing adventures! Join us for a memorable catch on the crystal-clear waters of the Cayman Islands.

Yellowfin tuna, wahoo, and mahi-mahi are all popular game fish caught in the Cayman Islands. Experience unforgettable Grand Cayman fishing for mahi-mahi! Join us for a thrilling deep-sea adventure in crystal-clear waters.