Karasumi Bottarga Japanese Mullet Roe Air Drying Nagasaki
Nagasaki, Kyushu; Edo period Chinese trade connection; also produced in Taiwan from grey mullet
Japanese karasumi is the local version of bottarga—salt-cured, pressed, and air-dried mullet roe sac—considered one of Japan's three great delicacies (Nihon Sanchin) alongside sea urchin (uni) and sea cucumber intestines (konowata). The name derives from a Chinese ink stick (kara-sumi) due to the finished product's resemblance in shape and color. Nagasaki became the production center during the Edo period through Chinese merchant trade contacts. The production process: fresh female mullet roe sacs are carefully removed intact, salted for 1-3 days (by weight percentage), rinsed, and then pressed between boards with progressively increasing weight while air-dried for 3-4 weeks, rotating and massaging daily to prevent mold and achieve even drying. The finished karasumi is deep amber-orange with a firm, waxy texture and intensely concentrated oceanic-umami flavor. It is shaved paper-thin over warm rice, sliced thinly with sake and daikon, or grated over pasta (the Japanese version of pasta with bottarga). High-quality Taiwanese karasumi from grey mullet caught during autumn migration is also prized. Storage in the refrigerator for months or frozen for up to a year maintains quality.