Common Onigiri Fillings

Rice triangles wrapped in seaweed with savory fillings are known as Onigiri or Japanese rice balls. You can have onigiri in a packaged form or handmade at grocery stores and restaurants. Onigiri rice balls are also known as omusubi. The name depends on the region. Instead of a triangular shape, onigiri can be circular. Sometimes they are not in seaweed and they have zany flavors like kalbi, barbecued beef, or curry from the Coco Ichibanya chain. 

Since ancient times, the Japanese have been taking rice in a ball form. The glorious reign of onigiri began in the Edo Period from 1603 to 1868. It began with the wrapping of nori or seaweed. The wrapping was to avoid sticky fingers. 

Common Onigiri Fillings 

The Japanese rice balls had a variety of fillings such as traditional pickled plum, tiny fish babies, or creamy seafood. 

Tuna Mayo

Chicken of the sea or tuna mayo is the most popular of onigiri flavors. It is one of the easiest onigiris to make. The creamy Japanese mayo makes it more delicious and creamier. This mayo is richer and thicker than western mayo. Tuna is another fish that is a very popular garnish for onigiri. The tuna shreds are extremely addictive. 

For a slightly more luxurious onigiri topping, look for chopped black or fatty tuna mixed with chives. You may recognize negitoro as a popular ingredient for sushi rolls. The main difference between negitoro onigiri and negitoro rolls is the onigiri version that uses regular salted rice instead of seasoned vinegar

Grilled Salmon Flakes

Salmon is probably the most essential onigiri garnish. When it is used for onigiri, it is called sake that is pronounced as Sha-Keh. In addition to salmon flakes, you will find salmon mixed with mayonnaise in onigiri. Salmon onigiri may have the most variation, but grilled salmon flakes have been one of the favorite toppings.

The flavorful, salty, and salmon flakes add a spicy sparkle to the surrounding rice. Onigiri is one of the Japanese foods that the moms cook for breakfast and lunch. Japanese also like to have it on picnics. 

Pickled Plum or Umeboshi

Another popular onigiri filling is umeboshi. It is a small and bitter pickled Japanese plum. You will find whole pickled plum or umeboshi paste in the center of your rice ball. While having umeboshi, you better watch out for the kernel.  Umeboshi is a particularly popular ingredient that you can eat during the summers. It is said to be good for summer heat exhaustion and fatigue. 

Umeboshi or pickled plum onigiri is relatively common in Japan and also appears in onigiri. Salty and dried plum tends to be an acquired taste for those who are not used to the strong flavor. If still, you are curious about the bitter and strong flavor, you can try umeboshi onigiri. Also, umeboshi onigiri is having a special three-part wrap to preserve the seaweed before you wrap it around the rice ball. 

Salted Cod Roe or Tarako

Salted cod roe is a lovely and sandy filling of onigiri. It is good for those who enjoy the subtle flavors of seafood. Sometimes people mix up tarako and mentaiko. Both are from the cod family but they are different. Tarako is a plain and salted ripe egg that is prepared and seasoned differently from the mentaiko. Mentaiko is a flavorful version and it is marinated. 

The tarako filling in onigiri is mixed with butter that gives the rice a savory and rich taste. 

Seasoned Cod Roe or Mentaiko

Mentaiko is almost like tarako but it is a salted cod roe. It is a common onigiri filling. Those who are having a spice phobia can try mentaiko topping because it produces a pleasant tingle. It does not burn or overwhelms. The powerful bite is softened by spreading over the rice. Also, it is perfect for a spicy moment without lasting much longer.

Some people season mentaiko with red chili pepper. When seasoned with red chili pepper, it is known as karashi. 

Dried Bonito Flakes or Okaka

Okaka is one of the old-fashioned onigiri fillings. It is a blend of bonito flakes flavored with soy sauce for a salty, bold, and smoky fish flavor. Umekaka similar to okaka or bonito flakes is mixed with umeboshi, for a sour and salty filling. If you have received a hot plate adorned with thin strips of paper dancing like the inflatable man at the car wash, you will know what bonito flakes are.

These dried tuna chips make a strong and smoky topping for onigiri. It is recommended for people who like to spend time by the grill during barbecues. Lawson’s onigiri is always smooth. It stays together without falling apart. As a result, you get fewer pieces of seaweed on your lap after a bite.

Kelp Simmered in Soy Sauce or Kombu

What better way to fill a seaweed-wrapped rice ball than with more seaweed? For the kombu onigiri, the tsukudani-dried seaweed leaves are cooked with soy sauce and mirin. Mirin is sweet rice wine. The blend is cooked until the hard kombu becomes tender and caramelized. The kombu can then be crushed or cut into thin strips and stuffed into a rice ball. This is a great onigiri option for vegans and vegetarians.

The kelp, or kombu, in onigiri, has a mild soy sauce flavor and a somewhat questionable, gelatinous texture. However, kombucha fans who want to try onigiri kombu are in luck. 

Grilled Salmon Cream Cheese

Sometimes new types of onigiri pop up in the stores or restaurants, just like this grilled salmon cream cheese flavor. It is not a crab ranger but a salmon. The cheese is inexplicably cubed inside the rice ball but it is not creamy. It is a safe and appetizing option if you are a sweet onigiri filling fan. 

Chicken Onigiri

For a more western filling, you can use chicken. A chicken-based onigiri is some kind of pilaf rice or you can say kara-age fried chicken onigiri. Like other seafood toppings and fillings, the chicken does not keep as well as them. For the perfect filling, make sure that you store it with an ice pack and serve or eat it soon after making or buying it.

Vegetable Onigiri

In addition to the ume-flavored and kombu onigiri, there are several options available for vegetable lovers, vegetarians, and vegans. The topping for vegetable onigiri includes sauteed takana that is a mustard leaf. Also, you can add matsutake mushroom, Negi miso, and daikon radish leaf with sesame oil. If you are using Negi miso, you can use miso soybean paste or Japanese leek. The colorful vegetables will make a tasty onigiri snack.

Prawn Onigiri

Another onigiri option is Ebi mayonnaise or prawn or shrimp with mayonnaise. It is similar to seafood salad. If you are a fan of shrimps or prawns, then you can particularly look for Ebi-ten musubi, also known as onigiri with fried shrimp in tempura.

Onigiri – A Rice Ball with Seafood Fillings

In addition to the plain salted rice onigiri, you will find several types of onigiri based on the type of filling it has. Some people like seafood, chicken or vegetables in onigiri. Also, it depends on the taste and flavor you want to have in onigiri. Onigiris is always a luxurious and rich option for any occasion.