Takuan (Rice-Bran-Fermented Daikon)

Variations

• This is fermentation with no brine. Fermentation reduces pickling to three levers — salt concentration, temperature, and keeping air out — and describes the third as "pressing everything under the liquid is the whole anti-mould strategy", with one litre of water and 20-25g of salt as the batch to start with. Takuan has none of that water. The radish goes into a dry bed of bran and salt, and the water pressed out of the radish itself wets the bran into a paste which is what excludes the air. All three levers are satisfied; the third by completely different means.
• The two to four weeks beforehand are what make that possible. A dried radish has lost about two-thirds of its water, so its water activity is low enough that spoilage organisms cannot establish even without full submersion — and there is little enough water left that what comes out only wets the bran rather than flooding the crock. Pack fresh radish in and you get a pool, diluted bran, and no barrier at all.
• The bran is a culture medium, not packing. Rice bran carries the sugars and vitamins the lactic bacteria live on, so the bed itself does the work. A Japanese household nukadoko — a bran pickling crock — is fed vegetables daily and handed down for decades on exactly that principle.
• The opposite strategy from kimchi and kkakdugi over one question: water. Kkakdugi cubes the same radish and coats it in a wet paste; kimchi salts in a 2-3 percent brine and makes its own liquor. Oi-sobagi scores and stuffs a cucumber, wet again. Takuan takes the water out first.
• The yellow slices in your gimbap are usually not this. As Korean Wikipedia notes, the danmuji sold commercially is generally daikon steeped in a salt or sugar solution — unfermented, and sometimes with sweeteners and colouring added. Traditional takuan is not neon yellow but a dull amber, and that colour comes from the bran and the months. It is the colour in the photograph on this page.
• Six pages here buy it. Gimbap, banh mi, bun cha, naengmyeon and jokbal all call for takuan or pickled radish as an ingredient. It is the same position currywurst occupies with a bought sausage, and this page is the step before it.
• The name is a person's name. The dish is widely said to have been devised by Takuan Sōhō (1573-1645), a Zen priest of the early Edo period. It is not a documented fact, but the Japanese name takuan-zuke comes from it.
• The quick version: slice the radish and steep it a day in salt, sugar and vinegar. Crisp and sharp, with none of the fermented smell and no keeping quality — but enough for a gimbap roll.
• Other bran pickles: cucumber, carrot, turnip and aubergine all go into the same nukadoko. They are not dried first, and they come out after a day or two. The drying is something you do only for a radish you mean to keep for months.

Tips

• Dry it until it bends. More reliable than counting days. Under-dried and the crock floods; over-dried and it turns leathery.
• Use raw bran. Roasted smells better and gives the bacteria less to eat.
• Pour in no liquid. It is the commonest mistake in this dish.
• Do not be shy with the weight. Liquid should have risen over the radish within a fortnight. If it has not, there is not enough weight on it.
• A white film can be skimmed; black or green mould means throwing the batch out. Scraping off the visible part does not help (fermentation).
• Wash off only what you are about to eat. Buried in the bran is the state it keeps best in.
• Slice it thin, 2-3mm. Cut thick, all you taste is the salt.