Karashi Mentaiko Born in Korea Not in Hakata
It is said that the opening of Shinkansen (bullet train) service to Hakata in Northern Kyushu was what made Karashi Mentaiko (spicy walleye pollack roe), a local specialty of Hakata, well-known throughout the country. That is, the Shinkansen passengers having bought the Karashi Mentaiko sold as a local specialty in the train or at the souvenir shops within the train stations talked about it as a “spicy hot specialty of Hakata” and thus spread it throughout the country.
Now, a lot of people may think that this Karashi Mentaiko was born in Hakata. The fact is, however, that Karashi Mentaiko was born in Korea. Every year, walleye pollack make their appearance in huge numbers along the Korean peninsula allowing for large catches of the fish. To enable the roe to be stored for a long period of time, one method used was to remove the roe from the female fish and then salt it. This was the beginning.
In Korean, walleye pollack is called myeongtae (mentai). In Japan, the word for egg, ko, is added to the end to form the word mentaiko. As such, it is a Korean word coined in Japan. On the Korean peninsula, the mentaiko is called myeongran jeots which means salted walleye pollack roe.
This myeongran jeots finally arrived in Japan in 1949 after the end of the war. The people of Hakata took this food that had been enjoyed by the Japanese living in Pusan before and during the war and tried various ways to prepare it so that it would suit the Japanese palate. The outcome was Karashi Mentaiko becoming the local specialty of Hakata.
Karashi Mentaiko and Tarako (cod roe) are different. However, as for both being walleye pollack roe, they are the same. Tarako is made by simply pickling the eggs with salt. By further flavoring the Tarako with liquid containing cayenne pepper, Karashi Mentaiko is made.
The image of Karashi Mentaiko is that of a souvenir from Hakata. However, Karashi Mentaiko has gone beyond simply being a souvenir and is now a daily staple in general households throughout the country. In fact, the yearly consumption of Karashi Mentaiko is around 30,000 tons at present. That is, the per capita consumption of Karashi Mentaiko is 12 servings a year (in terms of 20 grams of Karashi Mentaiko per serving).
Thus, the taste of the Korean peninsula reproduced as a local food in Hakata after the end of the war took a ride on the Shinkansen and conquered all of the dining tables throughout Japan.