What is Uni (Sea Urchin): Taste, Texture & How to Eat It

If you've ever been to a seafood market in Japan, you may have seen these spiky creatures hanging out in the bottom of a tank somewhere. This is uni, or sea urchin — a delicacy and revered ingredient in Japanese cuisine. 

Out of the 950 species of sea urchin, only 18 are edible. Of those, two are most commonly used in Japan: murasaki uni, with a dark purple shell and sweet, yellow insides, and bafun uni, flatteringly referred to as “horse poop uni” for its dark brown shell and orange meat filled with umami. Although consumed year-round, the peak season for uni runs from April to September.

When you eat uni, you’re just eating the fleshy part of the sea urchin — no spikes involved! The edible part is the gonads, the reproductive organs that produce eggs. Probably to make it sound more appetizing, Japanese people simply refer to this dish as “sea urchin roe,” similar to the cod roe onigiri you might like at the konbini.

In general, uni has a rich, custard-like texture, but the flavor is what divides people into the categories of loving or hating uni. Those who are more hesitant to try it might want to go for the murasaki uni first, as the taste is sweeter and less salty. Those who want to branch out should try bafun uni, with an umami and slightly bitter flavor profile. 

Whichever you choose, the most important thing is to have uni during peak season, otherwise the sea urchin will be watery and briny.

As the name suggests, uni sushi involves rice, sea urchin, and sometimes seaweed. Depending on the type of sushi, uni can be the main star or delicately balanced with other ingredients. 

The most basic form is nigiri sushi, where the chef lays a slice of uni on a bed of rice. Shiro uni, or the light yellow pieces from murasaki uni, are typically used for this thanks to the melt-in-the-mouth sensation it creates when you’re eating it. 

The most popular way to eat both aka uni (another name for bafun uni) and shiro uni is in the form of gunkan-maki, or battleship rolls. Here, the rice is wrapped with seaweed on the sides and piled high with chunks of uni, sometimes accompanied by wasabi, cucumbers, or caviar. 

If you’ve got the budget, uni temaki is another alternative. Intended to be eaten with your hands, uni temaki sushi involves a large piece of seaweed wrapped either horizontally like a hotdog bun or vertically like a crepe around rice with a sizable amount of uni — as much as three times the amount of regular sushi! Be prepared to spend up to $50 on a single piece of this luxurious sushi. 

An option to end the meal is hoso-maki, sliced sushi rolls with uni in the center. It’s typically served at the end of the meal but uni hoso-maki will probably just make you hungry for another round!

Find out more: Different Types of Sushi: Find Your New Favorite

Formerly known as “Sushi Saisho,” Ginza Saisho has made a triumphant return to Ginza to serve premium quality sushi at their secluded, intimate location. 

Drawing many visitors to the restaurant is the famous Sea Urchin Festival, held at irregular intervals and booked almost immediately upon announcing. The buttery and succulent uniku, combining the Japanese words for sea urchin and meat, is a trademarked specialty here.

Heading up this prolific eatery is Chef Saisho himself, a native of Akita Prefecture and an English speaker eager to chat with patrons from all over the globe. 

Easily recognized by its neon sign and proximity to Gotanda Station, Sushi Tokyo 81 serves up Edomae-style sushi with a nostalgic charm. 

Read as “eight-one,” this restaurant isn’t just popular for its fashionable aesthetics. The showmanship is also top-notch, as the chefs make most of the sushi right at the counter, including the traditional aged tuna and fluffy koshihikari rice treated with in-house red vinegar. 

Sushi Tokyo 81 is home to two signature dishes: abalone with liver sauce and sea urchin sushi, with uni sourced from Toyosu Market, Choshi Port in Chiba, and Oma Port in Aomori, ensuring you’re eating the freshest uni available. 

Sushi Iwase’s interesting story starts with a salaryman’s life-changing bite of sushi, which inspired him to become a sushi chef. After an impressive start training at some of Tokyo’s most established sushi joints, Chef Iwase Kenji opened Sushi Iwase in 2012. 

Rather than just sourcing his food from the local Toyosu Fish Market, however, Chef Iwase prefers to go the distance, sourcing the distinctly textured Mizuho no Kagayaki rice from Ishikawa and other ingredients all the way from Hokkaido and southern Kyushu. 

Speaking of the rice, it’s the larger grains and sheen that give Sushi Iwase’s sea urchin nigiri sushi a unique mouthfeel, complimenting the sweet and salty tang of the uni. 

Experience your life-changing bite at Sushi Iwase. 

All-you-can-eat sushi with impressive quality at a digestible price point — need we say more? Over a two-hour period, you can feast as much as you want on all types of sushi: nigiri, gunkan, maki and more. No need to worry about the sushi going cold as it runs in circles on the conveyor belt — all sushi is made to order! 

You won’t have to skimp on the more luxurious ingredients, either: Sushi Academy offers medium-fatty tuna, salmon roe, sea urchin and more in a central location, making it a convenient place to fill your belly and enjoy Japanese cuisine while sightseeing. 

Those with kids will be happy to know that discounts are available for children under 12 years old, with children three years old and younger dining at no cost. 

Taste the west coast of Japan without leaving the east coast at this Ginza oyster bar. 8th Sea Oyster Bar’s signature oysters are farmed at a depth of 300 meters in the fertile waters of Toyama Bay. Because they are farmed,  fresh oysters are available year-round for the patrons of 8th Sea Oyster Bar.

After being farmed, the oysters are purified in a 60-hour cleaning process, ensuring that they are safe and ready for consumption. 

It’s recommended to kick off the night with raw oysters (and a glass of your favorite alcohol) before diving into other oyster-inclusive dishes, such as the mixed rice with an uni topping and porcini cream sauce.

Named for the flower motif of the decor and, yes, even the food, Sushi Yon Hana radiates elegance from the moment you walk through the front door, where you’re greeted by lavender blooms and ikebana floral arrangements at every turn. 

Once served, you’ll notice the sushi is shaped like flowers too.  Slices of red tuna or sea urchin are formed into petals and topped with edible gold leaves. Although the marinated red bream or tare sauce-brushed conger eel will dazzle anyone, the freshness of the soft, floral-shaped, uni is the piece de resistance. 

Interested in more sushi and seafood-related content? Check out our beginner’s guide to sushi, affordable omakase sushi restaurants in Tokyo, the top sushi spots in Japan’s capital, or a guide to Toyosu fish market.