Japan — Niigata Prefecture, developed 1956; Koshihikari now the most widely planted variety in Japan accounting for approximately 35% of total rice acreage
Japan's rice culture is built on Japonica short-grain varieties bred specifically for the characteristics valued in Japanese cooking: high stickiness (amylopectin-to-amylose ratio), translucent appearance when cooked, slightly sweet flavour, and the capacity to hold shape in onigiri and sushi while remaining tender. The dominant varieties: Koshihikari (developed 1956, grown in Niigata, Fukui, and across Japan) is the gold standard — prized for its balance of stickiness, sweetness, and glutinous texture; Akitakomachi (developed 1984, grown in Akita Prefecture) is considered slightly firmer and less sweet, preferred in some northern regions; Hitomebore (Miyagi Prefecture) and Haenuki (Yamagata) are regional prestige varieties. Uonuma Koshihikari from the mountain regions of Niigata's Uonuma district commands the highest prices in Japan.
Clean, milky-sweet, slightly glutinous; the baseline flavour of Japan — against which everything else is measured
Rice freshness matters: newly harvested rice (shinmai, October–December) has higher moisture content and requires slightly less water when cooking; older rice becomes drier and needs more water. Rice polishing degree: standard (70% bran remaining), premium (95% bran removed). Store rice in a cool, dry, sealed container away from light — rice oxidises and absorbs odours. The washing ritual: rinse rice in cold water, swirling and draining 3–4 times until water runs nearly clear — this removes surface starch that would cause gumminess. Rest washed rice 30 minutes before cooking.
For the best tasting test of rice quality, steam a small amount with water only — no seasoning. Premium Uonuma Koshihikari from a trusted seller will have a slightly sweet aroma during cooking and a clean, mildly sweet flavour when eaten plain. Add a small piece of kombu (2cm square) to the cooking water for a subtle umami depth that becomes detectable only as an absence when omitted. For onigirazashi (non-wrapped onigiri): use rice slightly warm, not hot, for the best shape retention.
Over-washing rice until completely clear, which removes too much surface starch and produces dry, separating grains rather than properly cohesive Japanese rice texture. Using the same water quantity year-round without adjusting for shinmai (new rice) vs. older rice. Lifting the rice cooker lid immediately after cooking — the rest period (15 minutes) is essential for even moisture redistribution. Stirring rice when it's freshly cooked and still too wet — wait until the rest period completes, then fold gently with a rice paddle.
Tsuji, Shizuo — Japanese Cooking: A Simple Art; Japan Rice Growers documentation; Niigata Prefecture Agricultural Bureau publications