Udon

Udon is a Japanese wheat noodle made without alkali. Under Japanese rules fresh udon is wheat flour kneaded with water and cut, or processed after cutting. Hiyamugi, somen and flat noodles belong to the same group: all are made from the same simple dough.

What separates them is thickness. Dried noodles 1.7 mm or more across are called udon, 1.3 to 1.7 mm hiyamugi or thin udon, and below 1.3 mm somen. Flat noodles at least 4.5 mm wide and under 2 mm thick are hiramen, kishimen or himokawa. The same limits apply to hand-stretched tenobe noodles. The Japanese JAS standard for dried noodles allows flour with up to 0.4 % ash, starch, oil for coating, salt, matcha and vegetable powder. Udon dough can contain up to 8 % salt.

The best-known regional udon is Sanuki udon from Kagawa Prefecture, nicknamed the Udon Prefecture: it has more than 600 udon shops, and its noodles are known for their thickness and shape. Kagawa's mild, dry climate suited wheat, udon shops already appear on the Edo-period Kinpira Matsuri Zu screen, and today the prefecture is breeding its own udon wheat, Sanuki no Yume.

Why it matters to you. Udon contains wheat and therefore gluten. Unlike ramen it has no kansui, which is why it is white and soft.