What Is Cod Milt And How Do You Eat It?

"Milt" is a term you may have never heard before — and to understand what it is, you can think of it as a counterpart to caviar. There are many longstanding myths about caviar, but in essence, it is salt-cured eggs from female fish, and is also referred to as roe or hard roe. Milt is the male version: fish sperm encapsulated in a thin membranous sac. It has a soft texture that's described as similar to cream cheese, and is also known as soft roe.  

Milt can be harvested from fugu (puffer fish), anglerfish, monkfish, squid, and salmon, but by far the most common source for it is cod. Cod milt is consumed throughout Asia, and in Japan, it is considered a delicacy. The Japanese name for milt is shirako (meaning "white children"), and the cod version is known as tara shirako. Its appearance, texture, and taste have been compared to oysters or brains, which share a similar creamy and fatty quality (the latter was put to good use in Salvador Dalí's surreal avocado toast recipe).

Milt from different fish is a traditional food source in a wide variety of global cuisines. In Italy, tuna fish sperm is called lattume and is served with pasta. In Russia, herring milt is pickled and goes by the name moloka, and in British cooking, it's breaded and deep-fried and served on toast (it can also be pan fried in butter ). In Jewish and Polish cuisine, herring sperm is made into kratsborsht, a sauce that's served with salad or fish. 

Cod milt is a winter specialty in Japan, gathered during the spawning season, when fish reproductive organs are full of seminal fluid. Shirako from the region of Hokkaido is considered the best, harvested from the Sea of Japan. While different types of fish eggs in Japanese cuisine are available year round, fans of cod milt eagerly wait for the cold months when it becomes available at sushi restaurants, izakaya bars, and as street food from fish markets. 

Shirako's flavor is milder than you might expect, with notes of ocean brine and a touch of sweetness. Depending on how it's cooked, shirako can take on a custardy quality or smoky notes when grilled. For an unadulterated taste of pure cod milt, it can be served raw on rice and wrapped with nori seaweed as gunkan maki sushi (aka a battleship roll). Another preparation is to poach shirako in boiling water and serve it with citrusy yuzu ponzu sauce, with toppings like grated daikon, shiso leaves, and scallions. 

Another way to enjoy shirako is battered and fried as tempura, accompanied by tsuyu dipping sauce (made with soy sauce, bonito, and mirin). This produces a crispy outside while the inside remains soft and creamy. Other techniques include grilling the sperm sacs over charcoal (a technique called yakimono); cooking in a hot pot (nabe) with dashi broth, fish or meat, tofu, and vegetables; or steaming and mixing into chawanmushi egg custard.