Somen

Somen is the thinnest Japanese wheat noodle: under Japanese labelling rules, dried noodles less than 1.3 mm across are called somen. The dough is wheat flour, water and salt, kneaded without alkali, so the noodle stays white. In summer it is eaten chilled with a dipping sauce, in winter hot in broth as nyumen. ³⁶

Thickness, not dough. Somen, hiyamugi and udon share the same simple wheat dough and differ by diameter: dried udon is 1.7 mm or more, hiyamugi 1.3 to 1.7 mm and somen less. For hand-stretched tenobe noodles the line is drawn differently, and anything under 1.7 mm may be sold as somen or hiyamugi. Japan's JAS standard for dried noodles allows edible oil to coat the strands. ³⁴

Miwa somen. The best-known somen comes from Nara Prefecture and is on Japan's register of geographical indications. A dough of flour, salt and water is stretched into strips and left to mature, then repeatedly twisted and drawn into fine threads while edible oil is applied. The noodles are dried to no more than 13.5 % moisture and cut to length; machines have taken over some steps, but hand-drawing survives. ¹²

Thirteen centuries. The register traces Miwa's history back about 1,300 years to Omiwa Shrine, where noodle-making reportedly began to help people through famine and plague. A document of 1754 praises Miwa's snow-white threads that stay firm in boiling water. Every 5 February the shrine holds the Bokujo-sai ritual, which forecasts the somen price for the new season, and since 1965 production has spread across all of Nara. ¹²

Somen across Japan. Kanzaki in Saga has made somen for about 380 years, since a travelling monk from Shodoshima, nursed back to health there, taught a local peddler the craft; the town once had over 300 makers and is also a birthplace of machine-made somen. Shodoshima itself has about 200 makers. Handa somen from Tokushima, brought by boatmen via Miwa in the mid-Edo period, is a little thicker and firmer, and was made from November to March. ⁶¹⁰⁹

Cold in summer, hot in winter. For hiyashi-somen the noodles are boiled in plenty of water, drained and firmed in ice water to remove the sliminess, then dipped in men-tsuyu with ginger, myoga or shiso. In winter the same noodles go into hot broth as nyumen. In Kagawa, somen is simmered with eggplant, and in Okinawa it is stir-fried with spring onion, salt and soy sauce. ⁶¹⁰⁸

Somen for celebrations. Long, thin threads stand for happiness that goes on and on, so somen appears at feasts. In Ehime, tai somen puts a whole simmered sea bream on noodles laid out like waves and is served at weddings and 77th birthdays. Eating somen at Tanabata, the star festival, is said to date from the Muromachi period and spread to ordinary people in the Edo era. ⁷

Somen or soba? The two are often confused, but they differ in flour. Somen is pure wheat, so it is white, fine and contains gluten. Soba is a buckwheat noodle: under Japan's labelling code fresh soba must contain at least 30 % buckwheat flour, which gives it a darker colour and a nutty taste, though most soba also contains wheat. ³¹³

Why it matters to you. In the USDA database, 100 g of dry somen has 356 kcal, 11.4 g of protein and 1,840 mg of sodium, about 4.6 g of salt, because salt is in the dough. Cooked somen has 131 kcal and only 161 mg of sodium per 100 g: most of the salt goes into the water, so boil it in plenty of water and rinse. Somen contains wheat, a mandatory allergen on Japanese labels. ¹¹¹²⁵