Few dishes divide first-time visitors like shirako. To some it is the height of Japanese winter luxury; to others the description alone is enough to give pause. Either way it is worth understanding, because for a few cold months it appears on some of the best counters in the country.
What shirako actually is
Shirako (白子) is the milt — the sperm sac — of male fish, harvested when the sacs are full in the cold months. The two most celebrated kinds are:
- Tara shirako — cod milt, the more common and affordable version.
- Fugu shirako — pufferfish milt, rarer, richer, and treated as a true delicacy.
The texture is the point: soft, creamy, almost like a warm custard, with a mild and faintly sweet flavor rather than anything strongly fishy.
When to eat it
Shirako is firmly a winter ingredient, peaking from roughly December through February. Cold water is when the milt is fullest, and fugu shirako in particular is bound to the winter pufferfish season. As our seasonal sushi calendar shows, this is the same rich stretch that brings fatty yellowtail and pufferfish to the table.
How it is served
Kitchens prepare shirako several ways, and a good one may offer more than a single preparation:
- Raw, with ponzu and grated daikon
- Grilled (yaki shirako), which firms the surface and deepens the flavor
- Simmered or served in a light broth
- Deep-fried (age shirako), crisp outside and molten within
- In hot pot, folded into a winter nabe
Where to find it
Cod shirako turns up widely through winter — at sushi counters, kappo rooms, and izakaya. Fugu shirako is the prize, and it is best sought at a licensed pufferfish specialist, where only certified chefs may prepare fugu. In Tokyo, the Asakusa pufferfish house Miuraya is one place the winter fugu season, shirako included, is taken seriously.
If a creamy winter delicacy sounds like your kind of adventure, plan a visit between December and February and ask the chef what the day's shirako looks like.