Ikijime (killing fish immediately) & nerve removal

About Ikijime & nerve removal

Fish tightening work is a very important point concerning quality.

In general, how to tighten is a field tightening (how to tighten to kill by leaving live fish and how to kill by liberating fish in the ice water) and living (How to remove blood while cooling it). In our company, we will pull out the nerve by injecting air into the spinal nerve after living dead.

By doing this, you can euthanize the yellowtail, suppress unnecessary energy consumption caused by rampage, and let the umami ingredients such as ATP be preserved in the fish meat.

Ikijime machine that

aims at the vital part

with surgical precision

Catch landing without

giving fish stress

Sure nerve

removal with air

Necessary and sufficient

blood draining and cooling

Procedure of Ikijime & nerve removal

We have a production line covering everything good for the improvement of flesh quality such as                  ikijime & nerve removal, blood draining, and fish temperature management. Especially, the killing work is a very important point related to material quality. Therefore, we thoroughly manage this process to bring you fresh products.

Ikijime & nerve removal, ikijime only, freshness change when killing on site

Fish who lived down are not stressed, and because they drain blood, there is a marked difference from the field tightening in physical quality. In the case of wildfish, the fish suffers from excessive stress, excessive consumption of ATP in the body, lactic acid accumulates, it suffers damage to taste and freshness. Also, do not bleed, your body will become reddish and soft, the texture will be bad. Our fish can keep the best quality by doing both livestock and neuro-emphasis.

Substances that decrease with time such as ATP (ATP, ADP, AMP, and inosinic acid)

Fish meat contains a substance called ATP (adenosine triphosphate) that is generated by aspiration and that plays a large role in muscle contraction and heat generation. ATP is used as an index directly indicating freshness.

ATP is a source of muscle energy. Exhausting fish physically and mentally leads to the consumption of valuable ATP.


ATP after both Ikijime & nerve removal done

ATP after Ikijime done,but nerve removal not done

ATP after Nojime done,but nerve removal not done


Substances that increase with time such as inosinic acid (inosinic acid and hypoxanthine)

When fish die, their energy ATP decreases, and AMP and IMP that are umami (savory taste) components increase and accumulate. As time passes after that, inosinic acid and hypoxanthine are generated to decrease freshness. With these increased substances that cause freshness decrease, fish cannot be eaten as sashimi.


Inosine and Hypoxanthine after both Ikijime & nerve removal done

Inosine and Hypoxanthine after Ikijime done,but nerve removal not done

Inosine and Hypoxanthine after Nojime done,but nerve removal not done


K value that changes with time (K value up to 20% is a rough guide regarded as appropriate for sashimi)

K value indicates the proportions of HxR and Hx to all the ATP-related compounds (substances related to nucleic acid). It is widely recognized in Japan as a freshness index. Immediately killed fish have a K value of about less than 10%. K values of less than 20% are rough guides for raw diets such as sashimi.


K Value after both Ikijime & nerve removal done

K Value after Ikijime done,but nerve removal not done

K Value after Nojime done,but nerve removal not done


Mass processing line for draining blood and nerve extraction from  live fish

Fish can be quickly slaughtered and cooled by the efficient basket wiring work.

Computer management screen for sea baskets.

Trace No. The locations of each basket, size, types and elapsed days of the fish can be identified by colors. The management of the number of existing fish has been automated by computer.

Management of trace code(QR code)

The labels for each sea basket

the tags for classification

Tank trucks for yellowtails

Quick landing (From the sea basket to the tank trucks)

All automatic lift for raw fish

Circulation process using submersible pumps in icy salt water

A generator is installed in the tank truck for operating a submersible pump to forcefully circulate cold water in the tank. In this way, the temperature of the cold salt water can be kept constant and decrease the fish’s body temperature, as well as sufficient bleeding is possible. The fish can be transported to the factory while maintaining its freshness.



Rumi Japan
(Morimatsu Suisan Reito Co., Ltd.)

5-2-20 Tenpouzan-cho, Imabari, Ehime 794-0032



We have been operating as a seafood wholesaler in this favorable location for over forty years. Furthermore, as a seafood processor, we are now shipping our safe HACCP-controlled seafood products under the brand name of “Rumi Japan” throughout not only Japan, but also North America, Asia and Europe.

The driving goal of our company is to produce safe and secure food that we can provide to our children without worry, and to deliver the same quality food to consumers’ tables in Japan and around the world.

We are committed to the international promotion of Japan’s healthy dietary culture, in which we Japanese take great pride.

Although we are still small, it is our sincere hope to make our best effort and to communicate peacefully beyond national borders with peoples in other parts of the world through dietary culture.

We look forward to doing business with you.