Made with fluffy Japanese rice, chopped pickled plums, and sesame seeds, these Plum Rice Balls are THE BEST THING for a picnic and potluck! It‘s hard not to fall in love with the savory, tangy, and nutty flavor of these onigiri.
Mr. JOC and I started watching season 2 of the popular Netflix® show – Midnight Diner: Tokyo Stories so that we can re-create the recipes from the series. In Episode 3, an old man named Umejii went into the diner and requested for pickled plums. When the master handed him a plate, he ate 10 of these plums straight up! My mouth immediately watered and my face scrunched up, literally like a sour plum.
Then I glanced over at Mr. JOC sitting next to me. His face plain and he didn’t seem to show any sort of reactions. This simple scene was able to ignite such a strong response in me, but not my husband who obviously didn’t grow up eating ume plum. Isn’t it interesting how our mind reacts to the food memory we have?
Today I’m sharing the Plum Rice Ball (小梅のおにぎり) recipe that Umejii enjoyed eating in the episode. It would be fun if I could see your face scrunch reading about pickled plum in this post.
What is Plum Rice Ball?
In case you haven’t seen the show, the Plum Rice Ball is a triangle-shaped rice ball made of steamed white rice, chopped pickled plums, and sesame seeds, and cloaked in a sheet of dried nori seaweed.
Japanese Pickled Plum – Umeboshi
Umeboshi (梅干し) is a savory Japanese pickled ume plum and it’s eaten as a condiment or accompaniment for a bowl of rice, similar to tsukemono pickles or furikake rice seasoning.
Ume plums are salted, flavored with red shiso leaves, and then dried under the sun to make umeboshi. The ultimate companion for a bowl of plain steamed rice.
In general, there are two types of umeboshi made with different ume plums. The regular, bigger wrinkly pickled plum is called Umeboshi, and the smaller and plump umeboshi is called Ko Ume (小梅).
The pickled plums used in the Midnight Diner episode are Ko Ume. They are firm, tangy, salty, and come in a bright red color. You can often find these small red ume pickle in the middle of white steamed rice in a bento box. We call it “Hinomru Bento” (日の丸弁当), which represents Hinomaru (meaning “circle of the sun” representing a Japanese flag 🇯🇵).
Where to Find Ko Ume
I remember I used to see packages of small umeboshi at Japanese grocery stores, but when I decided to make the rice balls and looked for one, I couldn’t find it. I went to different Japanese grocery stores and they seem to disappear from the shelves. That’s strange, I thought. It shouldn’t be that popular that all the stores are sold out.
So I asked one of the staff when they would restock these pickles. And the lady said they can’t be imported any more due to the artificial red coloring used for the plums. It’s really unfortunate to see ingredient(s) that is not quite necessary being added to the foods that we feed our bodies.
In the end, I had asked my mother in Japan to send me a package of Ko Ume so I could make the recipe as close as what you see in the show. For your own enjoyment, please use the regular umeboshi that is healthier. The red color of the plums should come from only natural red shiso leaves, not additional artificial coloring. You will still yield the same flavors and faintly pinkish rice balls. The only difference would be the texture as regular umeboshi does not have the crisp crunch that Ko Ume is known for.
* I found out Nihon Ichiban sells these small crunchy Kari Kari Ume and Low Sodium Kari Kari Ume online. They ship internationally.
Tips on Making A Rice Ball
- Use Japanese short-grain rice – I can’t stress enough that you really need to use Japanese short-grain rice to make rice balls. Short-grain rice naturally sticks to each other once they are cooked. All you need to do is to gently press to keep all grains together.
- Wet your hands – It might sound silly to even mention it, but don’t touch cooked rice with bare hands. Rice just sticks to your hands and everywhere. Make sure that your hands are moist and that salt is applied to your hands to keep the rice balls safe at room temperature.
- Make the triangle roof – Holding a ball of rice in your left hand and making a 90-degree “roof” with your right index and middle fingers and your right palm, mold the rice into a triangle shape with gentle pressure.
- Rotate the rice ball – Press gently into a triangle rice ball shape while you rotate the rice ball so each corner gets a sharp 90-degree edge.
- Keep your rice ball at room temperature – With salt and sour pickles, the rice balls kept at cooler room temperature (61-68ºF, 16-20ºC) are safe to consume even after 6-8 hours later. Rice gets hard when kept in the refrigerator. If you really have to store in the refrigerator, wrap the rice balls with a thick towel to keep them cool, not too cold.
How to Serve Plum Rice Ball
In the “Midnight Diner: Tokyo Stories”, the old man Umejii enjoyed the plum rice balls on its own. However, you can pack them in your bento lunch box or serve them as an after-school or midnight snack. They are fabulous with a cup of green tea!
Other Popular Rice Balls (Onigiri) You’ll love:
- Cherry Blossom Rice Balls
- Tenmusu (Shrimp Tempura Rice Ball)
- Miso Yaki Onigiri
- Bulgogi Onigirazu
- Spam Onigirazu
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Plum Rice Ball
Ingredients
- 4⅓ cups cooked Japanese short-grain rice (make using 1½ cups or 2 rice cooker cups of uncooked rice)
- 3.5 oz pickled plums (ko ume) (use the small-sized variety with a firm, crunchy texture)
- 2 Tbsp toasted white sesame seeds
- 1 tsp Diamond Crystal kosher salt
- 3 sheets nori (dried laver seaweed) (Cut the nori sheets in thirds)
Instructions
- Gather all the ingredients. For the cooked rice, please note that 1½ cups (300 g, 2 rice cooker cups) of uncooked Japanese short-grain rice yield 4⅓ cups (660 g) of cooked rice. See how to cook short-grain rice with a rice cooker, pot over the stove, Instant Pot, or donabe.
- Remove and discard the seeds from 3.5 oz pickled plums (ko ume).
- Mince the plums with a sharp knife.
- Add the chopped pickled plums and 2 Tbsp toasted white sesame seeds to 4⅓ cups cooked Japanese short-grain rice.
- With a rice paddle, mix well together using a cutting motion. Don’t “stir“ the rice and make it mushy. Roughly divide the rice into 6 or 8 equal portions.
To Shape the Rice Balls
- Prepare a bowl of water and a bowl of 1 tsp Diamond Crystal kosher salt. Wet both hands and then dip 2 fingertips in the salt and spread between your palms.
- Scoop the rice onto your palm. Gently press and form the rice into a triangle. I use three fingers (thumb, index finger, middle finger) to make a triangle corner. Tip: For step-by-step photos and instructions on how to shape the rice balls using your hands, an onigiri mold, or plastic wrap, see my Onigiri recipe.
- When you press, your hands should be just firm enough so the rice ball doesn‘t fall apart. You don‘t want to squeeze the rice too tight.
- Wrap the rice balls with strips cut from 3 sheets nori (dried laver seaweed). Enjoy!
Can I make this with the pickled plums that are like way dryer if I cook them with the rice?? Or is soaking them in warm water enough?
Hi Carman, Thank you for reading Nami’s post and trying her recipe.
You can try soaking them in warm water, but the flavor of the Ume are different.
We hope this helps!
Thank you so much for this lovely recipe! My husband and I just recently tried onigiri from a local restaurant and loved them. Wanted to recreate this delicious treat as an easy one-handed snack for my husband to eat when he has to leave early for work (and for me to eat while pregnant and working from home too of course). Your delightful recipe did the trick. As you suggested, I used umeboshi instead of ko une, and they turned out great!
Hi Marie! We are so happy to hear you and your husband enjoyed the Onigiri! Maybe baby too!😊
Thank you very much for trying Nami’s recipe and for your kind feedback.
I also could not find Ko Ume (小梅). I asked at our local store (Uwajimaya). She called the ko ume, “fancy”. I tried to search for it online, but it just came up with ko ume candy. Any ideas if it can be ordered? She said it would hold together better in the rice.
Hi Bronwyn, Thank you very much for trying Nami’s recipe!
In this post, Nami posted Nihon Ichiban’s link. They sell these small crunchy plums internationally.
We hope this helps!
Hello Nami! I’m wondering if it is possible to replace white sesame seeds with black ones? Thank you!
Hi Emily! Thank you very much for trying Nami’s recipe!
The Black sesame seeds have a slightly nuttier and more bitter flavor, but if you prefer it, of course, you can replace it with.
We hope this helps!
Thank you! We just do the regular one plum on the back. This will be a better treat.
Don’t throw the seeds away! Crack them open and eat what’s inside 😀 we do this all the time.(for umeboshi)
Hi Yuki! Thank you very much for trying Nami’s recipe and for your kind feedback!
Can I make this with sticky rice?
Hi Sheilagh, Yes, you can make Onigiri(Rice Balls) with sticky rice. However, the texture and flavor of the rice will be different.
We hope this helps!
Could I use sticky rice with this?
Hi Sheilagh, Yes, you can use sticky rice to make Rice Balls.
Thank you for trying Nami’s recipe!
Really? I didn’t have good results with sticky rice at all! Tastes great but didn’t hold together for me. Will use short grain next time.
Love your recipes! There just aren’t enough days (even in a pandemic) to try them all. Can you tell me what the difference is between onigiri and omusubi? My Japanese friend was stumped.
Hi Linda! Thank you very much for your kind feedback!
Onigiri and Omusubi, There are various theories about the difference between the names. However, both are rice balls.
In most parts of Japan, it is called “Onigiri,” while some part in Kanto to Tokaido is often called “Omusubi.”
Some say it depends on the shape, and “Omusubi” is usually rice with a mountain/triangular shape, and “Onigiri” is the shape of the cylinder or can be in any form. We hope this helps!😉
I absolutely love these! The first time I ever had these were when I ordered them off of a Sushi Zushi menu. The savory and sour take combo do just as you say, make your mouth water and scrunch. I was sad when they were ultimately removed from their menu. I had to find a way to make them on my own, especially while I was pregnant. I had cravings for these things and I could not find any restaurant that sold these. I went to a local Asian grocery store and found a plastic jar of pickled plums in their refrigerator aisle, the short grain sticky rice, and to help with the molding process a triangle shaped rice mold to help me make the perfect rice ball every time. Needless to say I was super excited as I waited for the rice to finish cooking. After I made about six, I gobbled down three and saved the other three for a later time. They truly hit the spot. Thank you for sharing this recipe.
Hi Lailoni, We are glad to hear you love Plum rice ball! Thank you very much for trying this recipe and taking the time to write to us.💕
Hi Nami! I’m going to be making a batch of these today, but I had a quick question regarding using a onigiri mold to shape them. I find I can make onigiri very quickly and without needing to cool the rice much by using a mold, and of course it’s nice to have all of the onigiri a uniform shape. However, regarding the salt, would it be best to mix the kosher salt directly into the rice before adding the rice to the onigiri mold (and if so, should I follow the 1 tsp measurement here or reduce it a little bit)? Or should I still wet/salt my hands and continue to shape the onigiri after removing each from the mold? Thanks so much!
Hi Lisa! I would rub salt on my damp hands to re-shape the onigiri after using mold. 🙂 Don’t mix salt in. It won’t be the same amount. 🙂
Oh good, that’s exactly what I did, and they were so delicious! Thanks very much for the recipe and for your reply 🙂
I’m glad to hear that (and sorry for my late response!). 🙂
It looks like you don’t use vinegar to season the rice?
Hi Brock! No, we only add sushi vinegar to steamed rice when we make sushi. If you’re not making sushi, we never add sushi vinegar to rice. Onigiri or rice balls are not considered sushi, so we use regular steamed rice. More about sushi rice (the rice we only use for sushi) here.
https://www.justonecookbook.com/how-to-make-sushi-rice/
You’re a great Nami!
Thank you Marissa! 🙂
Wonderful! I’m really excited to start doing this season. I opened a file for the first season, now I’m opening it for the second season. And hand to hand.
Thank you very much for your attention. Thanks.
Hi Syd! I hope you enjoy Season 1 and Season 2 recipes on the blog!
Oh no wonder I haven’t been able to find ko ume! I look every couple months when I’m in the Bay Area!
Hi Patricia! You were looking for it too? I was checking for a few weeks before I decide to ask the staff. I thought it was just out of stock. You can use regular umeboshi for this recipe though. I don’t know why they can’t just make koume without all the food coloring! So sad.