Interested in learning how to make Onigiri fillings the authentic Japanese way? We have a bunch of Onigiri filling ideas to help you make Onigiri the right way.

What is Onigiri?

Onigiri also known as Omusubi or Nigirimeshi is a type of Japanese rice ball. However, it is often formed into a triangular shape which is then wrapped in a thin paper sheet of dried seaweed known as nori.

Historical Onigiri

Onigiri is a dish that has accompanied Japan throughout its long and illustrious history and is considered to be the original traveling food. This lightly salted rice which is then compressed into easy to handle single servings, with tasty Onigiri fillings inside has been found in backpacks or bento boxes of almost everyone from samurai, to infantry soldiers, travelers, to picnickers for centuries in Japan.

The first Onigiri to appear may have been more than just compressed salted rice. The widespread consumption of these rice balls meant that the form persevered the tasty Onigiri fillings and would later become a popular way of consuming rice throughout the years.

This dish has been present within Japanese food culture for centuries and throughout this time has gone on to take new designs and include different fillings. However even with all these new variations, the basis still remains much the same as the original from all those years ago.

Homemade Onigiri

There are a number of simple Onigiri filling ideas that can be used when it comes to making your very own Onigiri and Onigiri fillings such as making use of a mold. There are a variety of plastic molds that will not only help you perfectly shape your homemade Onigiri, but will also ensure that your Japanese rice balls are equally sized.

Another method would be to use a bit of kitchen plastic wrap in order to help you mold your Onigiri without having them fall apart in your hands.

Keep in mind that it may take a bit of practice when making your very own Onigiri creations for the first time. However don’t be intimidated about messing up as it will be an excellent learning experience when it comes to making your own Onigiri. One day you’ll be molding Musubi from the comfort of your own kitchen and will have gotten so good at it that you won’t even realize you’re doing it.

How To Make Onigiri Shapes

Start off by taking a full-sized sheet of nori seaweed and then cut it lengthwise into thirds. Next, be sure to wet your hands in water to keep the rice from sticking to them so that you can mold your Onigiri much more easily. Cup your wet palm to make a crater and then place about ½ cup of cooked Japanese rice in it. Then add about ½ tablespoon of your filling into the crater in your palm and then enclose it with the rice.

Now, mold the rice between your two palms into a triangular shape. Avoid pressing too hard, however it will need to be hard enough so that your rice keeps its shape. This might take a little practice but you should be able to get the hang of it quickly. Then sprinkle the exterior of the rice ball with a bit of salt and finish it off by grabbing a piece of already cut nori and wrap it around your rice ball.

If you’re making a variety of Onigiri with different fillings, then it’s best to place a bit of the filling on top of the completed rice ball, so that you can determine which is which, given how once finished, the rice balls all tend to look the same.

Fillings for Onigiri

We have some great Onigiri filling ideas for you now. Some of the more traditional Japanese Onigiri fillings will commonly use salmon roe, tuna mayo, spicy salted pollock roe, and simmered seaweed as there fillings of choice.

Below you will find a couple of Onigiri preparations in which the Onigiri fillings tend to lean towards the more traditional Japanese flavor profile.

Okaka is a savory combination of fillings that are fermented and use dried skipjack tuna or bonito flakes and soy sauce, possessing a deep and salty flavor.

Shiozake consists of salted salmon which has been oven roasted and flaked. This method of preparation provides a savory Japanese salmon Onigiri that really highlights the richness of the fish.

Mushroom and Scallions is a type of Origini that is prepared using finely chopped straw mushrooms which are then quickly pan sauteed with a bit of sugar, mirin and soy sauce. It is then finished with minced green scallions resulting in a variety of sweet and complex flavors.

Furikake is a rice seasoning mix, typically composed of dried ground fish, sesame seeds, seaweed and spices. This savory goodness is mixed in with cooked rice before forming the Onigiri itself.

That’s all you need to make delicious Onigiri and your favorite Onigiri fillings at home, it could not be easier!

Below we have some recommended rice and molds that you can purchase online. They will not only make your Onigiri authentic in taste but professional in look.

The Review

Nishiki Premium Rice

Nishiki Premium Rice

This California grown product is a medium grain rice whose flavor and texture is all too familiar for those who love sushi. With the use of a new technology called Musenmai, they are able to mill the rice perfectly. 

Through the use of this method, they are able to remove the tapioca from the rice and then make it sticky with liquid brine. Once the brine is removed, you will be left with a pure and cleansed rice, perfect for cooking and no longer requiring a second rinsing. This all natural product is by far one of the best sushi rice on the market, an excellent choice for those who plan on making various Japanese dishes for their meal time.

Nishiki Premium Rice

15 Pound Package

DAISO Simple Triangular Onigiri Rice Ball Maker

DAISO Simple Triangular

This highly recommended triangular shaped rice mold is incredibly simple to use, although there may be a bit of a learning curve when using different types of ingredients other than just rice. However there a number of online videos that can easily sort you out. 

The mold is made using a plastic with a non stick surface and is incredibly durable. Cleaning the mold itself is relatively quick and easy, making it a great product to have when making your very own Onigiri.

DAISO Simple Triangular

A rice ball mold

Mikasa Jones
Mikasa grew up in the dynamic Harlem neighborhood of New York City. Mikasa defines herself as an adaptive young woman who has been immersed into various cultures not just in the United States, but also her mother's hometown in Yokohama, Japan. She is a chef by profession and is an active member of the American Culinary Federation. She swears by a cup of hot matcha after a long day, saying that it helps her relax and focus on her tasks on a day-to-day basis.

Japan Daily Press is one of her outlets for sharing information with readers about the accessibility of commercially available Japanese products. She thinks that the misconception of sub-standard quality and taste of commercial food should be erased because there are a lot of manufacturers that are really stepping up their game in terms of developing products that are as close to authentic as possible.