Masago

Masago is the name of a food product—the roe of small fish called capelin (scientific name: Mallotus villosus). The roe consists of tiny eggs with an orange-red colour, and is most often used in Japanese cuisine such as sushi and maki. Capelin belongs to the family Osmeridae and lives in cold waters of the North Atlantic and Arctic oceans.

Masago is frequently confused with tobiko, which is the roe of flying fish. Tobiko is larger and has a crisp texture when eaten, whereas masago is smaller and produces a burst of flavour when bitten. Both are commonly coloured and flavoured with additives such as wasabi (green), squid ink (black), or beetroot.

Capelin

Capelin is a fish that typically grows to less than 20 centimetres in length. It feeds on plankton and serves as an important food source for larger fish such as cod, as well as for seabirds and marine mammals. This makes it a crucial link in the food chain of cold-water seas.

Capelin spawn by gathering in large numbers in shallow coastal waters or estuaries, where they deposit their roe on the seabed or gravel. This timing is essential for commercial fishing, because the roe is harvested when the fish are spawning.

Fishery and processing

Iceland, Norway, Russia, and Canada are the largest producers of capelin roe. The roe is separated, cleaned, and then dried and coloured. The rest of the fish is mostly converted into fishmeal and fish flour for animal feed and aquaculture. Annual catch limits are managed according to quotas based on marine research and vary considerably from year to year.

Nutrition and use

Masago contains protein, omega-3 fatty acids, and vitamin B12. It is also high in sodium, which comes from the cleaning and storage process. As food, it is added to sushi rolls and used for colour and flavour enhancement—it is not typically a food that people consume in large quantities at a single meal.