Ume Onigiri (梅おにぎり), also known as Umeboshi Onigiri, is one of Japan's oldest and most beloved rice balls. Made with fluffy Japanese short-grain rice and filled with umeboshi (salted pickled plum), this simple yet flavorful snack is a staple in Japanese homes, bento lunch boxes, convenience stores, and picnic meals.

The combination of warm rice and the tangy, salty, slightly sour umeboshi creates a refreshing balance of flavors that has been enjoyed in Japan for centuries. Traditionally, umeboshi was also valued for helping preserve rice, making Ume Onigiri a practical and delicious travel food.

What Is Ume Onigiri?

Ume Onigiri is a Japanese rice ball filled with umeboshi, a pickled Japanese plum that has been salted and often dried. Despite being called a "plum," ume is more closely related to an apricot and has a uniquely tart flavor.

Unlike sushi, Onigiri uses plain cooked Japanese rice without vinegar seasoning. The rice is lightly salted, hand-shaped into triangles or rounds, and wrapped with crisp nori seaweed for easy handling.

Its simple ingredients and bold flavor make it one of the most traditional varieties of onigiri.

Ingredients

For the Rice

  • 2 cups Japanese short-grain rice
  • 2½ cups water
  • 1 teaspoon salt (for shaping)

Filling

  • 4–6 umeboshi (pickled Japanese plums), pits removed

For Wrapping

  • 4–6 sheets nori (seaweed), cut into strips or halves

Optional Garnishes

  • Black sesame seeds
  • White sesame seeds
  • Shiso leaves
  • Furikake seasoning

Kitchen Equipment

  • Rice cooker or saucepan
  • Mixing bowl
  • Small bowl of salted water
  • Plastic wrap (optional)
  • Onigiri mold (optional)

How to Make Ume Onigiri

Step 1: Cook the Rice

Rinse the Japanese short-grain rice until the water runs nearly clear.

Cook according to the package instructions or in a rice cooker.

Allow the rice to cool slightly until warm enough to handle comfortably.

Step 2: Prepare the Umeboshi

Remove the pit from each umeboshi.

If the umeboshi is very large, cut it into smaller pieces.

Step 3: Shape the Onigiri

Wet your hands with salted water.

Place a handful of warm rice in your palm.

Make a small indentation in the center.

Add one umeboshi or a spoonful of chopped ume.

Cover with more rice.

Gently shape into a triangle, round, or cylinder without pressing too firmly.

Step 4: Wrap with Nori

Wrap the bottom or one side of each rice ball with a strip of nori.

If you prefer crispy nori, wrap it just before serving.

Step 5: Serve

Arrange the Ume Onigiri on a serving plate.

Sprinkle with sesame seeds if desired.

Serve immediately or pack into a bento lunch box.

Tips for Perfect Ume Onigiri

  • Use freshly cooked Japanese short-grain rice for the best texture.
  • Wet your hands frequently to prevent the rice from sticking.
  • Don't overfill with umeboshi, as its flavor is naturally intense.
  • Wrap the nori at the last minute for maximum crispness.
  • Use premium-quality umeboshi for the most authentic taste.

Popular Variations

Shiso Ume Onigiri

Add chopped shiso leaves to complement the tangy umeboshi.

Sesame Ume Onigiri

Mix toasted black or white sesame seeds into the rice.

Yaki Ume Onigiri

Grill the rice balls and brush them lightly with soy sauce for a crispy exterior.

Brown Rice Ume Onigiri

Use cooked brown rice for additional fiber and a nuttier flavor.

Furikake Ume Onigiri

Sprinkle the outside with furikake seasoning for extra umami.

What to Serve with Ume Onigiri

Enjoy these traditional rice balls with:

  • Miso Soup
  • Tamagoyaki (Japanese Rolled Omelet)
  • Grilled Salmon
  • Japanese Pickles (Tsukemono)
  • Edamame
  • Seaweed Salad
  • Green Tea or Roasted Barley Tea

Storage Tips

  • Enjoy freshly made Ume Onigiri within 6–8 hours at room temperature if kept in a cool environment.
  • Refrigerate for up to 24 hours, although the rice may become firmer.
  • Wrap individually in plastic wrap to help retain moisture.
  • Freeze without the nori for up to 1 month and add fresh nori after thawing.

Nutritional Information (Per Onigiri)

  • Calories: 190
  • Protein: 4g
  • Carbohydrates: 39g
  • Fat: 1g
  • Saturated Fat: 0g
  • Fiber: 1g
  • Sodium: 450mg

Nutrition values are approximate and vary depending on the size and saltiness of the umeboshi.

Health Benefits

  • Japanese short-grain rice provides lasting energy through complex carbohydrates.
  • Umeboshi contains organic acids that contribute its distinctive tangy flavor.
  • Nori is a good source of iodine, vitamins, and minerals.
  • Homemade Onigiri contains no preservatives and can be tailored to your taste.
  • A light, satisfying snack or meal that's easy to pack and enjoy on the go.

Frequently Asked Questions

What is umeboshi?

Umeboshi is a traditional Japanese preserved ume fruit that is salted and often dried. It has a distinctive salty, sour, and fruity flavor.

Is Ume Onigiri vegan?

Yes. Traditional Ume Onigiri is naturally vegan, provided the nori and seasonings contain no animal-based ingredients.

Why is umeboshi commonly used in bento boxes?

Its high salt and acid content has traditionally helped keep rice fresh, making it a popular filling for packed lunches.

Can I make Ume Onigiri ahead of time?

Yes. Prepare it a few hours in advance, wrap it well to retain moisture, and add the nori just before serving if you prefer it crisp.

Can I use flavored umeboshi?

Absolutely. Honey-marinated umeboshi (hachimitsu umeboshi) offers a milder, sweeter flavor while maintaining the classic taste of Ume Onigiri.

Final Thoughts

Ume Onigiri is a timeless symbol of Japanese home cooking, transforming simple ingredients into a flavorful and portable meal. The fluffy rice, tangy umeboshi filling, and crisp nori create a harmonious balance that has delighted generations. Whether packed in a bento, enjoyed on a picnic, or served as a quick snack, this authentic Japanese rice ball is a delicious way to experience the simplicity and tradition of Japan's everyday cuisine.