The Onigiri (Omusubi) FAQ

smileyonigiri.pngI have written quite exhaustively about onigiri, or rice balls, here on Just Bento as well as on Just Hungry. Many people have asked similar questions about onigiri, which seem to just be gaining and gaining in popularity these days. So I’ve assembled a list of Onigiri FAQs (Frequently Asked Questions). I’ll update this list when I see (or remember) other questions periodically.

Basics and culture

  • What is an onigiri? An onigiri is a savory (salty) compressed ball of rice. It often has a filling or a coating of something savory, but there are also onigiri made of pre-flavored/mixed rice, as well as plain rice onigiri simply made with salt.
  • How do you pronounce it? o-NI-gi-ri (short 0 at the top, not oh or ooh)
  • How is it written in Japanese? most often おにぎり (all in hiragana); very occasionally お握り
  • My Japanese friend/my Japanese grandmother/my Hawaiian uncle calls it something else… Onigiri are also often called omusubi (おむすび). Some more obscure regional names include nigirimama and oninko. You can also drop the honorific o and call it musubi, nigiri, or nigirimeshi (which literally means “hand-pressed rice”. What you call it just depends on where you grew up! In Hawaii, a rice ball is called a musubi mostly. There was a big wave of emigration from Japan to Hawaii in the late 19th century, mainly from the western/southern parts of the country, which probably accounts for the use of musubi.
  • Why do anime and manga characters love onigiri so much? Onigiri is Japanese comfort food, because Japanese people love rice. Rice is the main staple of Japanese cuisine. (In the movie Kamome Diner (kamome shokudo), discussed at length here, onigiri are called “Japanese soul food”, and I think that is very true.)
  • Does an onigiri have to be a triangle? No it doesn’t - it can be round, or cylinder shaped, or anything else. There are a few purists who insist that onigiri must be triangular, but I’m not one of them. See Onigiri on parade.
  • Where can I get onigiri in Japan? Just about every supermarket and convenience store sells them, not to mention train station kiosks, vending machines and more. They are as common as pre-made sandwiches are in the West. (Actually you can get pre-made sandwiches as easily too in Japan.)
  • Are onigiri just for bentos? In Japan, onigiri is a basic convenience food. People carry them on hikes, car trips, have them for breakfast, as late night snacks…etc.
  • Are onigiri a Japanese invention? They probably are, because of the nature of Japanese style rice (slightly sticky). This type of rice, also called uruchimai, came into wide use around the 11th or 12th centuries, and onigiri may have come into existence then. In China you have steamed glutinous rice wrapped in leaves, but that’s a bit different from onigiri. (see okowa onigiri made from sticky rice)
  • Is Spam Musubi Japanese? Spam musubi is a product of Hawai; it was probably created by immigrants of Japanese descent. Spam was virtually unknown until fairly recently in much of mainland Japan. (Spam is fairly popular in Okinawa, which was occupied until the 1970s by the United States and still has a U.S. military base. It’s also very popular in South Korea. Both regions, as far as I can find out, got their Spam habit from Americans.) Personally, I just can’t make myself like Spam in any form, so you won’t see any spam musubi recipes on this site - sorry! There are plenty of spam musubi recipes online however - see this one on Lunch In A Box, or this step by step on Cooking Cute.


  • How many calories are in an onigiri? It depends on how big it is or how much rice is used to make it. A typical onigiri has about 1/2 cup of rice, so it’s around 100 calories plus whatever is used for the filling.
  • Does an onigiri have to be made with white rice? You can also make it with brown rice, as long as it’s medium-grain Japonica rice or short-grain glutionous rice. See Looking at rice.
  • Are onigiri diet food? Well, that depends on how big they are! Many people find onigiri more filling than sandwiches, but that’s a subjective thing of course.

How to make onigiri

  • What’s the key to making good onigiri? The base ingredient of onigiri is the correct type of rice, cooked properly. A rice cooker can be very helpful for doing this. See how to wash and cook rice properly using a rice cooker or on the stove, and more about rice cookers.
  • Do I have to use Japanese rice? What about jasmine rice (or other types of rice)? An onigiri has to stay in a ball shape, so the rice has to be glutinous enough that the grains stick together. That means that long grain rice types like jasmine and basmati are not, I repeat not, suited to onigiri. (I feel very strongly about this.) Sure, mushy, overcooked rice will glue together if you mash it hard enough, but it will not taste nice at all. The most suitable types of rice for onigiri are medium grain or short grain. See Looking at rice for different types of rice. If you can’t get Japanese type rice (or ‘sushi’ rice) easily where you live, Italian rices used for risotto can be substituted.
  • How do I make onigiri? There are very detailed instructions for how to make them with your bare hands, plus an easier way using plastic wrap. JustBento reader Samantha contributed this great method of making onigiri in a plastic bag, using the corners! You can also use handy molds/moulds: Cooking Cute has a nice step by step tutorial. Recent onigiri molds come in a handy scooper shape which makes making onigiri in all kinds of cute shapes even easier. Example: these Hello Kitty molds, and the colorful mini onigiri I made with them.


  • Does an onigiri have to have a filling? No it doesn’t! The most basic type of onigiri is a shio musubi (塩むすび), a plain rice onigiri with salt on the outside. This is the kind of onigiri that was carried around in feudal times by samurai and foot soldiers on the warpath. It’s a great way to enjoy simple, well cooked good rice.
  • What are traditional onigiri fillings? A list and photos of the most common traditional fillings are on the Onigiri on Parade page. The top three traditional fillings are: umeboshi (pickled plums), shake (salted salmon - how to make your own from fresh salmon) and okaka (katsuobushi or bonito flakes flavored with soy sauce).
  • Non-traditional fillings? Anything you can imagine! Some suggestions that readers have made in the past include: chopped up olives, anchovies, pickles, a small meatball, cooked chicken, sausage meat, chopped up Spam, corned beef… as long as it’s not too wet, compact and a bit salty, anything can be a good onigiri filling.
  • Help! My onigiri fall apart! This could either be due to using the wrong kind of rice (long grain rice, jasmine rice, basmati rice, etc. are not sticky enough to make a rice ball with), improper cooking of rice (it should not be too dry/hard OR too sticky/gluey) or using a filling that’s so oily or watery that the oil/water seeps out into the rice, making it fall apart.
  • Do onigiri have to be wrapped in nori seaweed? No they don’t, though a wrapping does help to keep the rice together. Again see Onigiri on parade. If you want to go wrapping-less but your onigiri falls apart before you can eat it, try transporting them wrapped in plastic wrap. You can even buy special cute onigiri wrapping film!
  • I hate nori…alternative wrappers? A popular wrapper is salted fresh shiso leaves. (I must confess that when I was a kid, I hated nori! But now as an adult I love it, so it is quite possibly an acquired taste.) Other wrappers include tororo kombu (a thin, salty form of kombu seaweed) and usuyaki tamago (thin omelettes).

Onigiri safety and transport

  • Can I freeze onigiri, and if so how? Yes onigiri can be frozen very successfully. Just wrap them individually in plastic wrap (cling film), and then in a freezer box or bag to protect it from freezer burn. You can defrost the onigiri in the refrigerator gradually, at room temperature, or zap it in the microwave. See Keeping onigiri fresh and more Don’t keep frozen onigiri in the freezer for too long, or they will eventually get freezer burn.
  • How do I prevent onigiri from getting dried out? Keep them well covered/wrapped up.
  • How long do onigiri last in the refrigerator? How do you keep them safe to eat? This mainly depends on the filling as well as how much salt you use on the surface when you make the onigiri. If you use tuna with mayonnaise or any filling with mayonnaise in it, do not keep more than a day to be safe. If you use traditional fillings, especially umeboshi (pickled salty plums) they will last a lot longer, but no more than a couple of days. Umeboshi has natural antibacterial qualities, so is the ideal filling for onigiri that have to be held for some time - say, made the evening before to be eating or lunch on the road the next day.

    In any case, you should make onigiri with adequate salt on the outside, completely cooked fillings (never ever use raw/uncured fish or rare meat) and always use freshly cooked (ideal) or defrosted/reheated rice. If the weather is very warm and humid and you have used spoilable fillings such as tuna/mayo, consider packing your onigiri with an icepack (see Summer Bento Safety).

    You shouldn’t eat onigiri that has been around outside of proper refrigeration for more than a day. Anecdotally, I have eaten onigiri that was a day old (made the morning before and eaten for breakfast) that had been in packed in a paper back and thrown on the back seat of a car, not in a cooler, and survived without any problems (it was in the fall, not midsummer), but you shouldn’t do this regularly! The fillings used that time were umeboshi and salty salmon, for what it’s worth - no tuna-mayo or crab salad or other highly perishable filling.

    (I’ve seen a note on this page that blithely states that “you can store onigiri refrigerated for up to a week”. No you can not! Please, use common sense and be safe not sorry. )

Other questions

  • Can I use sweet fillings for onigiri? Fundamentally you can use anything you like - it’s your food! However, in Japan if you make a ball of rice (which is often sweetened itself, and pounded partly or fully to a sticky paste or dough) and filled with something sweet it becomes confectionery or wagashi. Some wagashi that take the rice-with-sweet-filling form include daifuku, mochi of various kinds, yatsuhashi and so on. The wagashi that’s closest to the idea of a sweet onigiri is probably ohagi or botamochi, glutinous rice “onigiri” of sorts which are filled, covered or both with sweet bean paste, kinako (toasted soy bean powder), sesame seeds and so on. So, to Japanese sensibilities an onigiri is something savory, not sweet.
  • What’s the difference between sushi and onigiri? Again it’s a matter of how things are normally categorized in Japanese cooking, but generally speaking anything made with vinegar flavored rice, or sushi rice (sushi meshi or shari) iis sushi. So you could make an onigiri-shaped item with shari, and call it an onigiri, but if a Japanese person ate it s/he would probably think it’s sushi in an onigiri shape. Nigiri-zushi, the best known sushi shape with a little ball of rice topped with fish or something else, is sushi that has been shaped with the hands (nigiru) - the same word that forms part of the word onigiri.

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Onigiri song

Sung to the tune of My Darling Clementine:

O-nigiri, o-nigiri o-nigiri kudasai

Cho oishii, asa gohan o-nigiri tabetai


Okay for those of us who don’t speak Japanese what does that mean?

Onigiri Japanese: Lesson 1

Sung to the tune of My Darling Clementine … sort of:

O-nigiri, o-nigiri, o-nigiri puh-lease (may I have).

Very tas-ty! F-or break-fast, I want to eat o-nigiri.

A bit choppy towards the end but I hope you could keep up ;-)

I accidentally sang *A bit

I accidentally sang *A bit choppy towards the end but I hope you could keep up* for the next verse!!!!! =-3


I just tried making Onigiri in my rice cooker and failed miserably... I rinsed the sushi rice in a seive, then put it in my Panasonic SR-DE-103 fuzzy logic rice cooker on the "sticky rice" setting... It cooked it for 50 min, but came out terribly gluey and sticky, and was on the verge on inedible. I tried to make some sort of onigiri but failed terribly and now I am sad, as there seems to be no specific accurate intruction for trying to use the rice cooker to make good rice. I am using shortgrain rice, and the settings I have to choose from are White Rice, Sticky Rice, Brown Rice and Quik Cook, as well as Steam, Soup/Cook, Porridge, and Cake...

Can anyone help me!!??


Many thanks,



The 'sticky rice' setting is the wrong one to use. You should use the White Rice setting. Sticky rice means short-grain mochi rice. See Looking at rice for an explanation of different kinds of rice.

This reminds me of this song

This reminds me of this song (sung to the tune of Frère Jacques):

hot potatoes, hot potatoes
soggy meat, soggy meat
sausages and bacon, sausages and bacon
doctor quick, I feel sick

(we used to since this when I was in school in England around age 7-8…)

I hope someday these catch

I hope someday these catch on in the US as widely as sushi has. Until then I’ll have to learn to make my own.

Discovered Just Hungry and this site via Slate’s piece on the Supersizers. Love both sites!

Love Rice

Starting high school and the school lunch there scares me. (Not like middle school and elementary didn’t scare me too…) But I’m really excited about getting back to school just so I can try out some new bentos and make some adorable onigiri! Thanks a ton you guys!!


Integrate what you know

I fried up some bologne and green onions to mix into my brown rice onigiri. It tasted wonderful and didn’t make the rice any less sticky, because the lunch meat is relatively lean. It’s not very traditional, but it’s tasty.

Probably an “old wise

Probably an “old wise (wives) tale”. I was told that the round musubi was used for funerals and the triangle shape was for regular use.

Onigiri shapes

Now that I’ve never heard… But there was an essay in a Japanese magazine I read recently, where the author said when he was growing up he always thought the onigiri his friend’s grandmother made were so much cooler than the ones his mother made. His mother’s were big and round and completely covered with nori, while his friend’s grandmother’s were triangles with just a small piece of nori. He even complained to his mother about how uncool her onigiri were. I guess it really depends on what you grew up with :)

Thanks for the info.

This is very interesting stuff. I love your cute Hello Kitty molds.


I’m in my second year of High School (10th Grade) and I hate school lunch, and the prices are rediculous! Not to meantion the temptation of a bag of chips or a soda at the checkout register. I didn’t even eat lunch in 9th grade because of this. But my doctor said that is unhealthy to go without breakfast (i have to wake up at 5 in the morning so the last thing I’m thinking about is food) and lunch and just eat dinner, and I completely agree. So I started making my own bento’s every night (it takes me about an hour with prep time, and cooking, and clean-up) last month, and since then, I’ve unknowingly be eating healthier, and I actually lost 5 lbs. In all fairness though, I also started working out 3 times a week, but I was told that the weight loss probably had a lot to do with my eating habits also. I’ve even made special bento boxes for my family members! These different tips on Onigiri have really helped me out this past month. Thanks a ton!

Wow - taking care of

Wow - taking care of yourself in the 10th grade is awesome! Good for you! You’ll be far ahead of everyone else for the rest of your life. (I shudder to think what I did to my body in the 10th grade… -___-)

Hehe, thanks. I just figure

Hehe, thanks. I just figure since were taking P.E. classes, why ruin all the work by eating unhealthy. Plus, Onigiri is pretty tasty :)

Re: The Onigiri (Omusubi) FAQ

ohhh! that's so smart. I ate the yucky school lunches plus tons of candy when I was younger (i know right maki)! making yourself bento sounds so awesome. Onigiri.. Japanese people have awesome ideas.

i'm a bit slow here but breakfast is a healthy addition to your diet too!

Re: The Onigiri (Omusubi) FAQ

Oh yeah I love reviving onigiri in rice cooker! 20 mins on keep warm in a little plate on top of the rest of our rice. My hand-made ones got loose but the ones from restaurants were perfect.

Re: The Onigiri (Omusubi) FAQ

I read the FAQ and i was wondering specifically if it is alright to make rice balls the night before and leave them out to be eaten through the course of the next day so as to not have them get cold. I know you said not to eat rice balls more than a day old but i was a little bit fuzzy on how to stored them.

Re: The Onigiri (Omusubi) FAQ

Onigiri can be stores well wrapped for a few hours after making them, but making them the night before and leaving them out may be problematic. If you have to make them the night before to be eaten the next day, select your fillings carefully, avoiding anything with mayonnaise and so on (like tuna/mayo), salt the outside of the onigiri well, and wrap each one completely in plastic wrap. Store them in the refrigerator until an hour before they are to be eaten, then take them out (still wrapped) to come up to room temperature.

Re: The Onigiri (Omusubi) FAQ

I'm going into 8th grade and my school has nasty non-nutritious lunches so I'm going to make me and my younger sister these for luch!!! Save money and be healthy!!!

Re: The Onigiri (Omusubi) FAQ

Im half Spanish and half Italian and I can make sushi like in the store and resteraunts! My Japanese friend stole it from my lunch on day -_-! I just hope I can make onigiri that good! I keep telling my mom I must have been full blood Japanese in my last life!

Re: The Onigiri (Omusubi) FAQ

I've tried this twice and both times my onigiri were very crumbly and wouldn't stick together. I washed my rice carefully, let it sit for 30 minutes, then cooked it. I was as careful as I could be with with rice-water ratio. Any guesses as to what I'm doing wrong?

Re: The Onigiri (Omusubi) FAQ

My guess is that you were either not using the right kind of rice, or very old and dehydrated rice.

Re: The Onigiri (Omusubi) FAQ

I've found that if you let the rice get too cold it doesn't mold as well - I prefer to mold it when it's still a little warm to the touch. Also, make sure your hands are really wet or the rice will stick and fall apart.

Re: The Onigiri (Omusubi) FAQ

Love your site, great recipes and idea's. We recently moved to the asian district of our city and having all these wonderful ingredients at our door have allowed us to expand from our normal Onigiri recipe (tuna mayo, and Shrimp Mayo) to include alot of the "classics" you mention..

One thing though. I work extensively with Food and theres a common misconception that your (unfortunataely) spreading. Mayo (even japanese mayos) that are commercial are VERY acidic foods, with an avarage Ph of 4.0 and some as low as 3.6 (more acidic than acid rain) and are EXTREAMLY safe to eat even after exposure to heat and moderate time. Bear in mind that mold and other bacteria can grow on it and thus spoiling it if left out for long periods of time(days) as well it can rend thus losing its acidic properties in the fatty portions and thus exposing itself too risk.

So if you like Tuna mayo onigiri and you want it to travel, use commercial mayos. Or Ensure that you add lemon(I prefer lime) juice to increase the Ph and thus extending the shelf life.

(Ps. The Ph of Umeboshi is 1.5 on avarage.. making it slightly less acidic then normal concentrations of sulfuric acid and slightly more than pure lemon juice. As determined via a titration of commercial Umeboshi)

Ps. Great site, and Im sorry to step on toes. Here's an article to substantiate my "claim"

Re: The Onigiri (Omusubi) FAQ

If I make Onigiri the day before, use a meat filling (meat balls, or teriyaki chicken), wrap and salt the outside very well, would it be safe to leave in the fridge overnight to be eaten at lunch time the next day? Friends have asked me to make them a bento, and cooking rice fresh in the morning takes so long with the half hour soaking time and so on. I have no room in the freezer.

Was thinking of nuking the Onigiri quickly in the morning then letting them cool again before packing them away.
Thank you.

Re: The Onigiri (Omusubi) FAQ

It should be okay if you cook the meat fresh the night before thoroughly (not using leftovers from like days before in other words!), and don't leave the onigiri out at room temperature for more than a few hours. If you want to be extra cautious, pack the onigiri along with an ice pack - the rice will be cold, which is not ideal, but being safe is better!

Re: The Onigiri (Omusubi) FAQ

As I do not want food poisoning to be my friend's first introduction to Bentos, I'm going to be very careful! :p

Thankyou for the swift reply and the help.

And now to master teriyaki chicken and tamagoyaki! My cooker is at a slight angle, so the egg flows to the back of the pan. :( Teriyaki with chicken breast meat turned out dry and oddly flavoured. Diff using thigh next time.

Re: The Onigiri (Omusubi) FAQ

i was always wondering is nigiri good for your heath?

Re: The Onigiri (Omusubi) FAQ

Well it is basically a ball of (usually white) rice, with some salt and a little you can decide whether that is healthy or not :)

Re: The Onigiri (Omusubi) FAQ

Does anyone know where the plastic wrapping that keeps the triangle onigiri seperate from the nori can be purchased online? I love the Japanese and Hawaiian style of the convenience stores selling premade onigiri with the plastic wrappings keeping the nori and rice seperate until just before consuming. But I can't seem to find the plastic sheets in bulk. Anyone help?

Re: The Onigiri (Omusubi) FAQ

J-list/JBox sells them. You can also try a single onigiri box, wrappng the rice ball itself in plastic and carrying a strip of nori outside of the plastic - here's how to do that.

Re: The Onigiri (Omusubi) FAQ

I just watched Kamome Diner; it made me so happy watching :)
Thank you for the tip!

Earlier today I made onigiri with salty chicked filling, they were ok.
I don't think I boiled the rice correct tough, my hands were véry sticky and mushy afterwards.

Congratulations on this great blog!

Re: The Onigiri (Omusubi) FAQ

I'm rather curious about the taste of umeboshi.

I just made my own onigiri yesterday and the only thing I could find that seemed close to umeboshi were plums in salt and water. I found it at a store selling chinese import food. I also forgot to salt my hands before shaping the onigiri, so there was no salt on the outside.

When I brought it out from the refigerator to eat it today the taste was rather interesting. I guess it would be better to eat this with salt on the outside as well.

Re: The Onigiri (Omusubi) FAQ

I love onigiri. I just made a batch and filled them with radish and celery kinpira (cooked with a dash of soy sauce). One is in the freezer, one is in the fridge, and the last one is gone. Who knew radishes were so tasty?

Re: The Onigiri (Omusubi) FAQ

Pressure-cooked Japanese-style brown rice (my preference is Koda organic) makes good onigiri—it's sticky like white rice. A little bit of cold water on the hands will make it even easier.

Re: The Onigiri (Omusubi) FAQ

I don't have a rice cooker at home. Can I still make onigiri properly though?
If you can help me please email me at airentear [at] yahoo [dot] com

Re: The Onigiri (Omusubi) FAQ

A rice cooker is not essential, but it's very useful and makes cooking rice foolproof. The page on how to prepare and wash rice, which is linked to above too, has instructions for cooking rice in a rice cooker or in a pan.

(Sorry I don't have the time to help people individually by email.)

Re: The Onigiri (Omusubi) FAQ

I'm sorry of this has been answered already (I did try to look):
Must I use salt when forming the onigiri? I have to limit the amount of sodium for our family for health reasons. If they aren't technically 'onigiri', that's okay. We would eat them within 2-3 hours.
Thanks in advance!

Re: The Onigiri (Omusubi) FAQ

You do not have to use salt but don't be surprised if they don't taste so good either.

Re: The Onigiri (Omusubi) FAQ

Am I able to use toasted nori, or is there a specific type of nori that I have to use?

Re: The Onigiri (Omusubi) FAQ

can pickled cucumber be a substitute for umeboshi?

Re: The Onigiri (Omusubi) FAQ

I am wondering about the pickled cucumber as well. I am trying to make my bento more traditional... sadly, when i don't pack it, it ends up holding crackers, cereal, cookies, some melon, and some vegetables. Also, I bring noodles made with garlic butter, probably not very traditional, but it tastes so yummy. :) This, along with rice when i pack it, gets mooched by my two friends. Today we fought over it, and two of us walked out of the lunch room with hands (I only had a pick, not good for long noodles) and the part of our faces closest to our mouths covered in garlic butter... Only upside, i kept smelling those yummy noodles for ten minutes of the next class. This summer I want to try making onigiri, but I am very (literally) picky about what I eat, which I am trying to overcome (this year was the first time since i was a toddler that I tried rice.)

Re: The Onigiri (Omusubi) FAQ

I purchased some 'Tono' furikake seasoning mixes and some rice-coloring stuff but cannot read the instructions on how to prepare them. I love the speckled rice look from blending furikake into rice completely, but is it blended before it's cooked or after? I have no clue about the 'Maruai Deco Furi furikaki' color mixes either. Can you give me any advice?

Re: The Onigiri (Omusubi) FAQ

is onigiri good cold? or is it better warm?

Re: The Onigiri (Omusubi) FAQ

I tried making a batch of these this weekend. I cooked the (medium grain) rice - complete with soaking step - as indicated in the instructions. I formed them using the plastic wrap method; however, the first one I tried removing from the plastic wrap fell apart. The FAQ says that one can use medium or short grain rice to produce onigiri, so I'm now wondering what could have made them fall apart (after the first, I just left the rest in the plastic wrap). Above, you say that it could be a case of very old and/or dehydrated. How can I tell if this is the case? I've since found out that my local Whole Foods sells Japanese rice, but I would like to know if this is something I can fix so I can use the medium grain rice I have on-hand before I go out an buy more rice. Thanks a bunch!

Re: The Onigiri (Omusubi) FAQ

Is the rice sticky enough to stick together? Try taking a few grains and pressing them lightly together; they should stick to each other (and to your fingers, if they are dry and not wet) easily. If not, your rice is somehow too dry. Do you use hot or at least very warm rice? Cold rice will not stick.

Re: The Onigiri (Omusubi) FAQ


I'm in love with japanese food, but only about 2% i'm afraid. :) I'm completely vegetarian; no meat and no fish!
I love plain onigiri and seaweed, and the pickles sometimes, but are there any good Vegetarian fillings you could recommend? Anything traditional, or just something that goes well with the onigiri?

Thank You!

Re: The Onigiri (Omusubi) FAQ

To me, it is the quintessential Onigiri: filled with umeboshi.

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