Fugu no Ko Nukazuke: Pufferfish Ovaries, a Japanese Delicacy

Kanazawa boasts a vibrant culinary landscape. One of its most intriguing offerings is fugu no ko nukazuke. This rare and traditional dish features fugu (pufferfish) ovaries— the most hazardous part of this delicacy. The preparation of fugu no ko nukazuke adheres to a strict traditional method, transforming this perilous ingredient into something safe for consumption. This exotic dish allows adventurous diners to savor the unique taste and texture of the fish while embracing the rich cultural heritage of Kanazawa’s local cuisine.

Fugu no Ko Nukazuke

In Osaka, fugu is a popular item, especially in winter. However, it is very dangerous to consume because the ovaries and the liver contain tetrodotoxin, a super poisonous substance. Even a tiny amount of it (0.5~2mg) is enough to kill one adult. 

For this reason, chefs must get a special license to cook fugu. The special chef carefully discards ovaries and liver; otherwise, the fish is very tasty. 

Only a few areas near Kanazawa, specifically Ono, Kanazawa (in Kanazawa City), and Mikawa (in Hakusan City), sell fugu no ko nukazuke, which is a pickled ovary of the pufferfish (fugu). The process of making this delicacy involves pickling the fugu’s ovary in salt for two years, followed by another year of pickling in rice bran (nuka). This lengthy pickling process helps to remove the toxins from the fugu, making it safe to eat. However, scientists do not clearly understand the exact mechanism that detoxifies the egg sacks. It remains unclear why and how the poison disappears.

One may still worry about food poisoning, but don’t worry! Health inspectors examine all products for toxicity, so there is no chance that you will accidentally take home something poisonous. Any products that have been tested have a sticker on them that says they have been inspected.  

Taste Check 

Fugu no ko nukazuke, as the name implies, is pickled in rice bran (nuka). While nukazuke has a refreshing pickled flavor, it also has a rather strong smell from the bran. Like other types of nukazuke, fugu no ko nukazuke is sold packed in the rice bran. Therefore, upon opening the package, you may notice a quite pungent odor from the rice bran. 

If you are not a native Japanese and are unfamiliar with strong-smelling Japanese foods, you might find the intense aroma off-putting and consider giving up at this point. 

If you visit Kanazawa, you may see blocks of this pickled delicacy available in stores. However, it is common for people to slice it and enjoy only a few pieces at a time.

The flavor is extremely salty, which is unsurprising after two years of curing. There is very little fishy smell, but it has a distinctly unique taste. The texture is similar to that of cod roe. You can enjoy it over rice as part of a dish called ochazuke. 

I believe this is best with alcohol, although this food might be too exotic for many people—some may be hesitant to even try it. The taste tends to leave a potent lingering flavor in your mouth, making it quite a unique experience.

If you want to sample just a bit, you might want to order it at an izakaya in Kanazawa. However, I think many non-native Japanese people, or even those not from Kanazawa, may need a bit of courage to try this dish. I can only imagine that the first person who ate fugu ovaries was exceptionally brave, or foolish. Maybe both?