Soy Tuna-Mayo Onigiri Recipe

Soy Tuna-Mayo Onigiri is a rice ball made with soy-flavored rice and filled with a mixture of canned tuna and mayonnaise. Compared to the regular Tuna-Mayo Onigiri, the rice in this version has a saltier taste. The lightly sweet and savory soy-flavored rice pairs well with the tangy taste of the tuna-mayo filling. This is another popular type of onigiri sold at convenience stores and onigiri shops in Japan.

What’s Soy Tuna-Mayo Onigiri?

Soy Tuna-Mayo Onigiri is a rice ball made with steamed rice seasoned with mentsuyu (a multi-purpose Japanese sauce) and shaped into triangles or simple rounds. It is filled with a mixture of canned tuna and Japanese mayonnaise and can be wrapped in nori (roasted seaweed) for added texture and flavor.

The regular Tuna-Mayo Onigiri is the most popular type of onigiri sold at Japanese convenience stores, with rice simply seasoned with salt. Soy Tuna-Mayo Onigiri is a flavorful variation of the original, featuring a rich, savory taste from soy sauce with a hint of sweetness. Its delicious umami flavor has made it an increasingly popular choice, just like the classic version.

Ingredients, substitutions, and tips for Soy Tuna-Mayo Onigiri

• Mentsuyu is commonly found in Japanese grocery stores and is often used as a dipping sauce for noodles like soba and udon—but it’s much more than that. This versatile seasoning mix can be used to flavor stir-fried vegetables, nimono (simmered dishes), sumashijiru (clear soup), and many other dishes.
• Store-bought mentsuyu comes in two types: straight and concentrated. The straight type can be used as is, while the concentrated version should be diluted with 2–3 parts water. If you’re using bottled mentsuyu for a recipe, look for the concentrated type. Or, if you prefer homemade, we have an easy mentsuyu recipe in our collection.
• No time to make mentsuyu? No problem! Simply combine 1 tablespoon each of soy sauce, mirin, and sake, bring them to a brief boil, and you’ll have a quick mentsuyu substitute.
• Canned tuna comes in different varieties, but any type will work. Tuna flakes are inexpensive and eliminate the need for mixing with mayonnaise compared to solid tuna. The tuna mixture may seem too soft for an onigiri filling, but its smooth and creamy texture is key to achieving a melt-in-your-mouth experience.
• Japanese mayonnaise is the important ingredient for the dish, but if you don’t have it, just use American mayo adding some lemon juice and salt.
• If it’s hard to shape Onigiri by hands, use plastic wrap to avoid the rice to fall apart.

What to serve with Soy Tuna-Mayo Onigiri

• Miso Soup with Soy Milk
• Miso Soup with Kimchi and Tofu
• Miso Soup with Tofu and Onion

More recipes like Tuna-Mayo Onigiri

• Onigirazu
• Tuna-Mayo Onigiri