What are you making with mochi rice?
- Making mochi (rice cakes): steam mochigome 25–30 min after a 4–8h soak, then pound with usu (mortar) or use a mochi machine — this is the primary use of mochigome and the reason the grain exists as a distinct variety
- Sekihan (red bean rice): cook mochigome and azuki together — the red colour from the azuki transfers during cooking, and mochigome's sticky starch makes the rice cohesive and festive; served at celebrations and auspicious occasions
- Ohagi or chimaki: sweet rice confections made from steamed mochigome formed with anko (sweet red bean paste) or wrapped in bamboo leaves — mochigome's cohesion and moderate elasticity before full pounding makes it ideal for these shapes
- Regular eating rice: use regular short-grain japonica — koshihikari, akitakomachi, or hitomebore — mochigome is not interchangeable with table rice and produces an unpleasant, overly sticky result in everyday bowl applications
What mochigome is
Mochigome is a variety of Oryza sativa japonica — the same species as regular Japanese table rice — but with a fundamentally different starch gene expression. Where regular short-grain rice produces amylose and amylopectin in roughly an 18:82 ratio, mochigome produces virtually no amylose. The result is a grain that is 99–100% amylopectin by starch composition.
When cooked, amylose contributes to the structural integrity that keeps individual grains distinct and firm. Without it, mochigome grains become gelatinous, opaque, and highly cohesive — individual grains lose their separate identity and merge into a sticky, elastic mass. This is not a cooking error; it is the intended result and the property that makes mochigome useful for its specific applications.
Common mochigome varieties include Hiyokuamoshi (Kyushu), Hakucho-mochi (Hokkaido), and Kinnohada. In export markets, mochigome is typically sold under the labels "mochi rice," "sweet rice," or "glutinous rice" — none of which refer to flavour sweetness.
For the full landscape of Japanese rice varieties and where mochigome fits, see Japanese Rice Varieties or the Rice hub.
Why the starch is different: amylopectin explained
Rice starch is built from two molecules: amylose and amylopectin. Amylose is a relatively straight-chain polymer that retrogrades ( recrystallises) quickly when cooked rice cools — this is what makes leftover rice hard. Amylopectin is a highly branched, tree-like molecule that retrogrades more slowly and is responsible for stickiness, cohesion, and the glassy appearance of freshly cooked sticky rice.
Regular short-grain Japanese rice is already higher in amylopectin than long-grain varieties like jasmine or basmati — this is why Japanese rice is stickier and softer than those types. Mochigome takes this to the extreme: with virtually no amylose at all, the starch behaviour shifts from "sticky with individual grains" to "gelatinous mass with no visible grain structure."
This also explains why mochigome is steamed rather than boiled. When regular rice is boiled, water enters the grain gradually and the starch swells evenly. Mochigome in boiling water absorbs moisture so aggressively, and the amylopectin behaves so differently under heat, that the result is uneven — gummy on the outside, undercooked in the centre. Steaming applies heat through vapour more gently and evenly, producing a consistent result.
How to cook mochi rice
The two rules that apply everywhere else in Japanese rice cooking — water ratio and soak time — apply here in very different proportions. Mochigome requires a much longer soak and much less cooking water than regular rice.
Quick ratio reference
Soak: 6–8 hours in cold water; drain before cooking
Steaming: 45–60 min in a bamboo or metal steamer; stir once at the 25-min mark
Rice cooker: mochigome/sweet-rice setting; 1:1.0 water ratio (not 1:1.1 — significantly less water than regular rice)
Steaming method (preferred)
- Rinse mochigome 2–3 times until water runs mostly clear
- Soak in cold water for 6–8 hours (overnight works well); drain thoroughly before cooking
- Line a bamboo or metal steamer with cheesecloth or a clean cotton cloth; spread the drained mochigome in an even layer
- Steam over high heat for 45–60 minutes; check water level in the base halfway through
- At the 25-minute mark, open the steamer and stir the mochigome gently to ensure even cooking — the outer layer cooks faster than the centre
- The rice is done when all grains are translucent, cohesive, and no longer opaque or chalky in the centre
Rice cooker method
Select the mochigome or sweet-rice setting if available. Use a 1:1.0 water-to-rice ratio — noticeably less than the 1:1.1 used for regular white rice. Soak 6–8 hours before cooking. Do not use the standard white rice setting, genmai setting, or any setting not designed for mochigome — the programme timing and water ratios differ enough to produce incorrect results.
Find mochigome (Japanese sweet rice) on Amazon →
→ Full stovetop and rice cooker method for regular Japanese rice: How to Cook Japanese Rice
What mochi rice is used for
Mochigome's applications are specific and defined by its starch behaviour. It is not a general-purpose grain — it belongs to a precise category of Japanese cooking and confectionery.
Mochi (rice cakes)
The primary use. Mochigome is steamed, then pounded in a usu (wooden mortar) with a kine (mallet) in a rhythmic two-person process called mochitsuki, or processed in a household mochi machine. The pounding breaks down the individual grain structure entirely and works the amylopectin into a smooth, elastic, homogeneous mass. The resulting mochi can be formed into shapes, filled with anko, coated in kinako, grilled, or served in ozoni soup.
→ Mochigome also makes exceptionally creamy amazake: How to Use Amazake
Sekihan (red bean rice)
Mochigome cooked with azuki beans, where the red colour from the azuki transfers into the rice during cooking. Standard ratio: 300g mochigome to 50g dried azuki beans. Simmer the azuki in 600ml water for 25 minutes until just tender; use the red-tinted cooking liquid to cook the mochigome. The stickiness of mochigome makes sekihan cohesive and slightly glossy — a texture specific to this dish. Sekihan is a festive food served at celebrations, weddings, and seasonal occasions.
→ Koji connects mochigome to fermentation: What Is Koji
Ohagi and chimaki
Ohagi are rice sweets made from lightly pounded or hand-formed mochigome wrapped in anko, sesame, or kinako. Chimaki are steamed rice dumplings wrapped in bamboo leaves — in Japan, typically made with mochigome and sweet fillings, associated with Children's Day (May 5). Both rely on mochigome's cohesion before the full pounding stage of mochi production.
→ How rice connects to koji fermentation and amazake: What Is Koji
Mochi rice vs regular Japanese rice
| Mochigome (mochi rice) | Regular Japanese rice | |
|---|---|---|
| Amylose content | ~0–1% | ~16–20% |
| Amylopectin content | ~99–100% | ~80–84% |
| Texture when cooked | Gelatinous, opaque, extremely sticky — individual grains lose structure | Tender, slightly sticky — grains remain distinct |
| Water ratio | 1:1.0 (rice cooker); steam preferred | 1:1.1 (stovetop or rice cooker) |
| Cooking method | Steam 45–60 min after 6–8h soak; or rice cooker mochigome setting | Boil → simmer 20–25 min after 30 min soak |
| Primary use | Mochi, sekihan, ohagi, chimaki | Everyday bowls, sushi, onigiri, okayu |
| Substitutable? | No — starch behaviour is fundamentally different | No — will not produce mochi-style texture |
Storage
Store uncooked mochigome in an airtight container away from light, heat, and humidity — the same conditions as regular white rice. Polished mochigome keeps 6–12 months in good storage conditions. Because mochigome is typically sold in smaller quantities than table rice (it is used for specific occasions rather than daily meals), freshness is generally easier to maintain.
Cooked mochigome — whether steamed for sekihan or pounded into mochi — should be eaten the same day or within 24 hours. The amylopectin in mochigome retrogrades differently from regular rice starch: freshly made mochi is soft and elastic, but it hardens significantly within hours as the starch cools and recrystallises. Hardened mochi can be grilled, added to soups, or dried — but the soft, fresh texture does not return with simple reheating.
Frequently asked questions
Can I substitute mochi rice for regular Japanese rice?
No — the starch composition is fundamentally different. Mochigome is nearly 100% amylopectin with virtually zero amylose, which means it becomes gelatinous, opaque, and extremely sticky when cooked. Regular short-grain Japanese rice contains 16–20% amylose alongside amylopectin, which gives it the familiar light, separate-grain texture. Using mochigome where a recipe expects regular rice will produce a dense, sticky mass rather than a bowl of tender japonica grains. They are not interchangeable.
How do I cook mochi rice?
Soak mochigome in cold water for 6–8 hours. Steam in a bamboo or metal steamer for 45–60 minutes, stirring once halfway through to ensure even cooking. If using a rice cooker, select the mochigome or sweet-rice setting and use a 1:1.0 water ratio — significantly less water than regular rice. Do not cook mochigome using the standard rice cooking method (boiling in water at 1:1.1 ratio) — the texture will be uneven, gummy in places, and undercooked in others. Steaming is the traditional method and produces the most reliable result.
Why is it called 'sweet rice' if it's not sweet?
The 'sweet' in English 'sweet rice' comes from the archaic meaning of the word 'sweet' as 'without bitterness' or 'mild and pleasant' — similar to 'sweet' water meaning fresh water rather than salt water. It refers to the absence of any bitter or sharp quality, not to flavour sweetness. In Japanese, the name mochigome (もち米) refers to its use in making mochi, not to any flavour descriptor. The Japanese word for sweet is amai (甘い), which is not part of the name. Mochigome is no sweeter in flavour than regular short-grain rice.
What is the difference between mochi and mochigome?
Mochigome is the uncooked grain — the raw rice. Mochi is the finished product. To make mochi, mochigome is first steamed until fully cooked, then pounded vigorously using a wooden mallet and usu (wooden mortar) or processed in a mochi machine until the grain structure breaks down entirely and the starch becomes smooth, elastic, and homogeneous. The transformation is complete: cooked mochigome still looks like individual grains; pounded mochi is a cohesive, stretchy, opaque mass with no visible grain structure remaining.
Can mochi rice be used to make amazake?
Yes — brown mochigome (genmai mochigome) makes a nuttier, creamier amazake than regular white rice or genmai, because the higher amylopectin content converts more fully into glucose under koji enzymes. Use the same ratio as white rice amazake: 200g mochigome to 100g fresh koji and 200–300ml water, held at 58–60°C for 8–10 hours. The result is sweeter and thicker than regular rice amazake. White (polished) mochigome can also be used and produces an even smoother result. Either way, mochigome amazake requires no sugar — the enzymatic conversion produces sufficient sweetness.
Can I mix mochi rice with regular rice for everyday cooking?
Yes — in small proportions. Adding 10–20% mochigome (by weight) to regular short-grain Japanese rice produces a stickier, more cohesive result without the full gelatinous texture of pure mochigome. This blend is traditional in some regional Japanese cooking and is used for onigiri where extra cohesion is desired. Beyond 20–25%, the mochigome starch begins to dominate and the texture shifts noticeably. Soak the mochigome and regular rice separately for different durations (6–8h for mochigome, 30 min for regular) before combining, or accept slightly uneven hydration.
Where to go next
- Cook mochi rice step by step: How to Cook Mochi Rice — soak, steam, or rice cooker method with exact ratios and timing
- Make amazake from mochigome: How to Use Amazake — mochigome's high amylopectin converts completely under koji enzymes, producing a sweeter, creamier amazake than regular rice
- Understand the koji fermentation engine: What Is Koji — how koji connects mochigome to amazake, mirin, and the broader role of rice starch in Japanese fermentation
- Understand the broader sticky rice family: What Is Sticky Rice — Thai, Chinese, and black glutinous varieties compared to Japanese mochigome, with the 0-2% amylose science explained
- Compare all rice varieties: Japanese Rice Varieties — where mochigome, koshihikari, akitakomachi, genmai, and haigamai all fit in the Japanese rice landscape
- Cook regular Japanese rice: How to Cook Japanese Rice — the 1:1.1 ratio and 30-min soak for everyday short-grain japonica
- Return to the rice cluster: Rice hub — full cluster map and all rice pages