Soba is the Japanese name for buckwheat. It usually refers to thin noodles made from buckwheat flour, or a combination of buckwheat and wheat flours (Nagano soba). They contrast to thick wheat noodles, called udon. Soba noodles are served either chilled with a dipping sauce, or in hot broth as a noodle soup.
In Japan, soba noodles are served in a variety of settings throughout Japan, but are also served by expensive specialty restaurants. Markets sell dried noodles and men-tsuyu, or instant noodle broth, to make home preparation easy. There are a wide variety of dishes, both hot for winter and cold for summer, using these noodles.
Soba can nutritionally complement other grains like white rice and wheat flour. Thiamine, missing from white rice, is present in soba. Soba contains all eight essential amino acids, including lysine, which is lacking in wheat flour. The tradition of eating soba arose in the Edo period.