Japanese Oysters: Milk of the Sea

Available on the market from November into early spring, oysters are a very popular food in Japan. Known as a wintertime ingredient, oysters are often served as a nabe (hotpot) ingredient. Rich in nutrients, they are nicknamed the “milk of the sea.” In many food cultures, oysters are also considered to be an aphrodisiac.

Oysters come in various sizes. The general rule of thumb is that small and medium-sized oysters can be consumed raw, whereas large oysters should be cooked unless stated otherwise. Famous oyster-producing
areas include Hiroshima, the Sanriku Coast, and Hokkaido, with varying production seasons ranging from fall to early spring.

There are two main types of oysters in Japan: rock oysters and Pacific oysters.

Rock oysters

Rock oysters are in season during the summer months of June through September. The shells are thicker than Pacific oysters, and the size and weight of the oysters are also larger. Since they are larger oysters, they are said to taste more briny and have a juicy plump texture. Some rock oysters are cultivated but most are natural, making them rarer and more expensive than cultivated oysters.

Pacific oysters

Pacific oysters are in season from November to April and are available all year round, fresh, cooked, or frozen. They are smaller in size compared to rock oysters. In Japan, the season for eating oysters depends on the type of oyster, but since most oysters on the market are Pacific oysters, the season is generally recognized as winter.

Popular Oyster Dishes in Japan

Fried oysters or "kaki furai" is a very popular oyster dish in Japan. The dish is made by breading the oyster, then deep frying it. It is often served with a side of cabbage, lemon, and tartar sauce. 

Hot pots are also very common in Japan, especially during the colder months, and having them with oysters is a wintertime favorite. In Hiroshima, it is called “kaki no dotenabe,” and is regarded as a speciality. The nabe consists of vegetables, tofu, and oysters that have been simmered in a broth. The dish is prepared in an earthenware pot that is lined with miso bean paste and lemon on the side.

Although more popular and commonly found in Chinese cooking, oyster sauce is another way to consume oysters in Japan. Adding oyster sauce, such as our Kesennuma Bay Oyster Sauce, to stir-fry will give the dish a unique umami flavor.

Due to its complex ocean currents and proximity to lush forests, Kesennuma Bay in Miyagi Prefecture produces some of the highest-quality oysters in Japan. The oysters for Kesennuma Bay Oyster Sauce are harvested one-by-one by skilled workers between March and late May just before spawning season (instead of the typical winter season), as this is when the oysters are at the plumpest. Only the highest-quality oysters are chosen, which means once they are sold out, you have to wait an entire season for the next batch. And unlike most oyster sauces that use just the boiled oyster broth, our producer, Ishiwata Shoten, uses the whole oyster for a more robust flavor and savory umami taste. 

About the author: 

Samantha Kwok

Samantha is currently a 5th-year JET in Okinawa, originally from Hawaii. She has been somewhat connected to Japanese culture her whole life despite being Chinese American. She's had the privilege of traveling to Japan and experiencing Japanese culture at a young age. She loves food and is always looking to try new places. When she is not working or out eating, she is an avid baker at home and has been known to feed her colleagues an excessive amount of baked goods.