ゲストコーナー：お米のプロの目線からのおにぎり情報

How the 2026 New-Crop Rice Turned Out

According to Shirai, this year's shinmai is exceptionally good across Japan, with more than half of the national harvest already completed. Some regions saw delayed harvests due to prolonged rain and a shorter-than-usual summer, and a few areas suffered flood damage—but the fact that temperatures never became oppressively hot worked strongly in the rice's favor. Shirai also noted that the latest varieties have been bred for heat resistance, meaning extreme summer temperatures no longer affect quality as dramatically as they once did.

Three Rice Varieties Especially Suited for Onigiri

Shirai was emphatic: "Virtually all Japanese rice varieties are suited for onigiri." The reason lies in the breeding process itself—compatibility with bento boxes and onigiri has long been one of the selection criteria, so only rice that clears that bar ever reaches market as a named variety. (Jasmine rice, indica, and other non-japonica types fall into a different category, which is why she said "virtually.") Within that field, she singled out three varieties.

**Iwafune Koshihikari**: Iwafune (岩船) is one of Niigata's three great rice-producing regions, alongside Uonuma and Sado. Koshihikari is a renowned variety, but flavor varies considerably by origin—making side-by-side comparisons a pleasure in themselves. The Iwafune version has a satisfying grain texture while still being soft, with a well-balanced sweetness. It stays delicious when cold, making it the quintessential onigiri rice. Studio tasters praised it as "sweet" with a "distinct grain feel."

**Sakihocore (サキホコレ)**: An Akita newcomer that debuted in 2022, giving it about four years of history. It was developed from Akitakomachi over nine years of breeding. Shirai described it as "a beautiful rice"—each grain is large and substantial, delivering a real sense of satisfaction, with rich stickiness, aroma, and sweetness. Versatile enough to handle both a simple salt onigiri and boldly flavored fillings, it is now widely available in Tokyo supermarkets.

**Nikomaru (ニコマル)**: Grown mainly in western Japan—particularly around Kochi and Fukui—and less familiar in the east. Its round, large grains produce a plump, satisfying mouthfeel when shaped into onigiri. Shirai became interested after two separate rice-shop acquaintances independently named it their personal favorite; after trying it herself she fell for a richness she described as different from, and complementary to, Koshihikari.

Other options: Milky Queen (ミルキークイーン) and Yumegokochi (夢ごこち) for lovers of a chewy texture; Haenuki (はえぬき), Shinnosuke (シンノスケ), and Yukiwakamaru (雪若丸) for those who prefer distinct, separate grains; and Sasanishiki (ササニシキ) for a clean, light finish.

The Golden Rule: Eat New-Crop Rice Within One Month

Shirai stressed this firmly: the moment shinmai is in hand, eat it within one month. Many people plan to use up leftover older rice first before opening a new bag—but that, she said, is a mistake. Shinmai's distinctive aroma and moist freshness are fleeting; leave it sitting and it becomes "just good rice." She compared it to sashimi: "Please eat it quickly." Older rice has plenty of uses later, so new-crop rice should always take priority.

For shinmai, a simple salt musubi is best. In the studio the team tasted salt onigiri made with new-crop Iwafune Koshihikari—100 g of rice and a pinch of salt placed on cling wrap, shaped, then wrapped with one-third of a sheet of nori. Shirai added that sweetness and aroma come through most clearly when the onigiri has cooled to about body temperature.

Older Rice Is Perfect for Takikomi Gohan and Mixed Rice

Older rice (from the 2025 harvest or earlier) has different structural characteristics from shinmai and is actually better suited for takikomi gohan (seasoned rice cooked with toppings), mazegohan (mixed rice), and sushi. Because shinmai's tissue is still soft—"like a baby," in Shirai's words—stirring or mixing it tends to make it mushy. Older rice has firmer grains that absorb cooking liquid well and hold their shape when tossed. "New-crop rice has its strengths; older rice has its own," she said. She also warned that after November, older rice tends to disappear from supermarket shelves, so those who enjoy takikomi gohan or sushi should stock up now.

The studio served a **beef-and-maitake takikomi onigiri** made with 2025-harvest Koshihikari, inspired by Korean chumoekbap (チュモッパ). The recipe makes 3 onigiri from 1 go of rice. Knead 50 g thinly sliced beef scraps and 50 g maitake mushrooms with soy sauce and sugar (1 tbsp each), sesame oil (1 tsp), and a small amount of grated garlic, then microwave at 600 W for 2 minutes. Pour only the cooking juices into the rice cooker along with 1 go of washed rice, add water up to the 1-go line, place the solids on top, and cook. Once done, fold in 10 g julienned takuan, 1 tsp white sesame seeds, and half a sheet of Korean nori torn into pieces, then shape as desired. Tip: if using fattier meat, switch to Japanese nori or reduce the sesame oil to make shaping easier.

About the Book

Noriko Shirai's book *Soup Jar and Onigiri Bento* (スープジャーとおにぎり弁当) is on sale now for ¥1,320 (tax included). The collection pairs soup-jar recipes with matching onigiri for efficient morning bento preparation.