SIGN UPLOG IN
TRAVEL TIPS
Beginner’s Guide to Common Onigiri Fillings
By Emily Suvannasankha
March 10, 2020
Updated: August 26, 2020

Japanese rice balls have a special place in my heart. To date, I’ve always gotten myself through the harrowingly long flight from the US to Japan by envisioning those beautiful triangular friends with their savory onigiri fillings waiting for me upon my arrival. I love them to the point of owning cute rice ball-themed dishware. (Read on to witness their majesty.) I do not exaggerate when I say: I do it for the rice balls.

Much like a sandwich, onigiri are versatile, delicious, and the perfect quick lunch when your salaryman “lunch hour” is really six minutes long. But often foreigners have trouble deciphering the litany of onigiri flavors available in Japan, as many of them aren’t common ingredients in Western cuisine. So let’s explore those konbini shelves; the seaweed awaits!

What is an Onigiri?

Shelves of onigiri at the konbini

Onigiri, or Japanese rice balls, are rice triangles wrapped in seaweed with usually savory fillings, often eaten as a fast meal or portable snack in Japan. You can get them anywhere you look, from packaged at convenience stores to handmade at grocery stores and even specialty mom-and-pop onigiri shops.

Onigiri rice balls, also called omusubi depending on region, are wildly customizable. Some are circular instead of triangular, some have no seaweed, and some have zany flavors like Korean barbecued beef (kalbi) or curry from the famous Coco Ichibanya chain. Here we’ll outline the classics—including how they’re written in Japanese, for the kanji-illiterate among us—as well as some newcomers!

Brief History of Onigiri

People in Japan have likely been taking their rice in ball form since ancient times. But the glorious reign of onigiri as we know them began in the Edo Period (1603-1868), when people started wrapping them in seaweed, or nori, to avoid sticky fingers on the go. Japanese rice ball fillings have since come to include a variety of flavors, from traditional pickled plum to creamy seafood to tiny fish babies (er, cod roe).

Happily for us modern folk, onigiri are now sold at Japanese convenience stores everywhere for only 100 to 200 yen. But you can also make them yourself pretty easily—and remember, as far as fillings go, anything you can stuff into a handful of rice is fair game.

Common Onigiri Fillings

1. Tuna Mayo (Sea Chicken, シーチキン・ツナマヨネーズ)

Tuna mayo onigiri on a backdrop of small onigiri rice ball illustrations

Tuna mayo onigiri—amusingly the “chicken of the sea” in Japanese—may in fact be the most popular of all onigiri flavors, not to mention one of the easiest to make. Always delicious, the creamy Japanese mayonnaise (thicker and richer than Western mayo) complements the tuna shreds in a way that is dangerously addictive.

This particular onigiri seaweed wrapper was hugging the rice ball kimono-style, giving it a charming v-neck. When the nori comes already touching the rice like this, it’s softer than when it’s protected by a special plastic wrapping.

2. Grilled Salmon Flakes (Yaki-shake/Beni-shake, 焼鮭・紅しゃけ)

Hand holds out an onigiri with a bite taken out of it, revealing the center of grilled salmon

Salmon onigiri come in perhaps the largest number of variations, but grilled salmon flakes has been one of my favorite fillings ever since I illiterately picked one up as a wee youngster.

The salmon flakes, salty and flavorful, lend a tangy brightness to the rice surrounding them. When I’m not writing articles about all the onigiri flavors, you can usually find me happily munching on one of these first two options.

3. Pickled Plum (Ume, 梅)

Classic umeboshi (plum) onigiri sitting on the shelf at a convenience store

Umeboshi, or pickled Japanese plum, is relatively common in Japan, popping up in onigiri as well. The dried and salty plum tends to be an acquired taste for those not used to its punchy flavor, so definitely pick this one up if you’re feeling curious (and perhaps brave)!

Also, the onigiri below has a special three-part wrapper to preserve the seaweed before you wrap it around the rice ball yourself. This results in wonderfully crunchy nori that softens after a minute or so.

4. Salted Cod Roe (Tarako, たらこ)

Onigiri packaging reading Pollack Roe and Butter

Salted cod roe is a gritty and pleasant filling, good for those who like subtle seafood flavors in general. Don’t mistake tarako with mentaiko—while both cod roe, this one’s the non-spicy one!

The onigiri pictured mixes tarako with butter, as they sometimes do, giving the rice around it a tasty richness.

5. Seasoned Cod Roe (Mentaiko, 明太子)

Mentaiko seasoned cod roe onigiri on a backdrop of a plate with onigiri illustrations

Of all the common onigiri fillings, seasoned cod roe is definitely the spiciest. But good news for the spice-phobic: mentaiko tingles pleasantly, but doesn’t overwhelm or burn. The powerful pang mellows out by distribution through the rice, perfect for a spicy moment without it lasting long past that.

6. Dried Bonito Flakes (Okaka, おかか)

Okaka onigiri rice ball with a filling of dried bonito flakes

If you’ve ever received a hot dish garnished with what look like thin strips of paper dancing like the inflatable man at the car wash, you know what bonito flakes are. These dried tuna shavings make a strong, smoky filling to onigiri, recommended for people who like to hang out near the grill during barbecues.

Hot tip: The nori on Lawson’s onigiri is always nice and smooth! It stays together without crumbling, making for fewer bits of seaweed on your lap post-nibble.

7. Kelp Simmered in Soy Sauce (Kombu, 昆布)

Kombu onigiri with a filling of simmered kelp

What better to fill a seaweed-wrapped rice ball with than more seaweed? The kelp, or kombu, in onigiri has a mild soy sauce flavor and gelatinous, somewhat questionable texture. Nevertheless, kombucha fans who want to try kombu onigiri are in luck; you can usually find kombu still hanging out on the shelves come the end of the day.

On yet another seaweed-related note, 7-Eleven’s nori wrapping, pictured here, tends to be quite textured and crumbly compared to that of Lawson and Family Mart.

8. Grilled Salmon Cream Cheese (焼サーモンクリームチーズ)

Pink packaging of a grilled salmon cream cheese onigiri

Sometimes new kinds of onigiri pop up in the convenience store rotation, like this grilled salmon cream cheese flavor I found at my local Lawson. 

It’s no crab (ahem, salmon) rangoon, as the cheese inside is inexplicably cubed, not creamy. But it’s a safe and palatable choice, so if you’re looking for a sweet onigiri filling, you could do worse than the ol’ seafood-and-cream-cheese standby.

9. Chicken and Vegetables (Torigomoku, 鶏五目)

Chicken and vegetables torigomoku onigiri

If you’re ever in need of a hearty, filling meal that you can fit in your jean pocket, definitely go for a torigomoku onigiri. These rice balls are packed with chicken and veggies like carrot and onion, soy sauce flavoring, and an oddly satisfying thickness unique among onigiri varieties.

To identify torigomoku onigiri, look out for dark rice, a circular shape, and a truly Thanksgiving-like bounty of chicken and vegetables on the packaging.

Honorable Mention: Devil’s Onigiri (Tempura Batter & Green Seaweed, 悪魔のおにぎり)

Limited edition Devil's Onigiri from Lawson with a raccoon character on the packaging

It’s common to find special, often limited-time onigiri with wacky names and packaging popping amongst the comparatively austere regulars. For example, Lawson’s exclusive “Devil’s Onigiri,” filled with tempura batter and, yes, green seaweed again, offers a rich and savory innovation on the classics. 

More flavors from this brand, like Dan Dan Noodles, Red Bean, and Okonomiyaki, are always making the rounds—just look for the angry, Halloween-ish raccoon who looks like he’s trying to sell you something.

Onigiri are always a splendid option for any occasion, whether you’re looking for a cheap thrill or just need to stuff your face with something edible. If you’re trying to find a particular flavor, search for a specific word, such as ume or tarako, within a longer description on the packaging. The names of onigiri flavors vary between stores and can get quite kanji-heavy!

My only other advice? Grab them fast! You can bet the salarymen will have run away with all the tuna mayo by nightfall—and you don’t want to be the poor sap stuck with kelp.

Feeling hungry? Browse Japanese home cooking classes or check out our YouTube channel!

0
Click clap if you like this post
Emily Suvannasankha
Masquerading as a grad student in Linguistics, Emily can typically be found counting the minutes ‘til her next peach chūhai. She has two years in Nagoya before her need for jumbo peanut butter sends her crawling back to the US.
You may also be interested in
Stay in the Loop!
We are always discovering the latest foodie trends.
Sign up to receive insider tips about the food scene in Japan's most extraordinary areas.