Takuan

Sun-dried daikon, its moisture drawn out, is pickled in rice bran and salt. Lactic bacteria and yeast in the bran bed are said to give it a distinctive sourness and depth of flavor, and it's treated as the pickle most identified with the whole bran-pickling family. Different daikon varieties bring different pungency and fiber, so drying and pickling both vary by region, and so does the resulting color, aroma, and bite.

Harvested daikon is sun-dried under the eaves for several weeks until it softens, then layered in a barrel with alternating dustings of rice bran and salt. Weighted down and left to ferment for several months, it develops takuan's characteristic aroma and bite. Some regions add sugar or malted rice to the bran to adjust the sweetness, others smoke the daikon before pickling it — the range of drying and pickling methods runs wide.

It is widely credited, among other accounts, to Takuan Soho, an early-Edo Rinzai monk said to have either devised it or simply favored eating it. Sun-drying daikon before pickling it in bran and salt allowed for long storage, and the method is said to have spread nationwide along Edo-period highways. Where a particularly pungent daikon variety is used, the resulting pickle sometimes even earns its own local name.