Japanese nameすんき
In Nagano’s Kiso region, sunki turns red turnip greens, sunki starter, warm liquid, and lactic fermentation into a winter taste for pickles and soba.
Information last updated 127 days ago
Sunki, also called sunki-zuke, is a salt-free lactic-fermented pickle made from red turnip greens in Nagano’s Kiso region. In the deep mountain valley far from the sea, salt was once difficult to obtain, so local practice shaped another route to flavor: blanching turnip greens, layering them with sunki starter, adding warm liquid, and keeping the vessel warm until acidity develops. The taste comes from leaves and fermentation rather than salt, vinegar, or soy sauce.
Kiso lies deep in the mountains of Nagano, and the area around Mount Ontake is far from the sea. In that setting, sunki turned red turnip greens into a preserved food whose acidity could serve winter meals. It is also treated within Nagano’s folk-cultural and regional food heritage contexts; the concrete practice behind those designations is Kiso people working with winter greens, warmth, starter, and lactic fermentation.
The main material is the leafy part of red turnips grown in the Kiso area. Six local Kiso turnip lines give that ingredient base a visible map: Otaki turnip from Otaki Village, Kaida turnip from the Kaida Plateau in Kiso Town, Kurose turnip from Mitake in Kiso Town, Yoshino and Ashijima turnips from Agematsu Town, and Hosojima turnip from Kiso Village. The practical name boundary is also tied to turnip greens grown in Kiso and production carried out in Kiso.
The work begins with washing and cutting the turnip greens, followed by brief blanching. While the greens are warm, they are layered with sunki starter, covered with warm liquid, and placed somewhere warm for fermentation. The starter carries one batch into the next: older examples include fermented wild pear or mountain grape, while current practice can use previous-year sunki that has been dried or frozen.
Many pickles rely on salt, but sunki is made without salt and without vinegar or soy sauce. Lactic fermentation lowers pH, improves keeping quality, and gives the red turnip greens a clean sourness. The process keeps attention on leaf fiber, fermenting aroma, and acidity, while showing how a mountain valley once conserved scarce salt through a winter vegetable technique.
Finished sunki can be eaten as it is, and it is also added to hot soba. Sunki soba and toji soba are associated with winter in the Kiso Valley, where sour greens meet hot broth and the aroma of buckwheat noodles. The making season from late autumn into winter links the pickle to cold-weather red turnip greens, household meals, and local noodle bowls.
Kiso communities continue the practice through cooking lessons, hands-on programs, fairs, and sunki contests. A Nagano transmission project included a recipe collection, cooking classes, and a contest that had continued from 1995 to its 20th edition; entries came from Kiso elementary, junior high, and high schools, as well as a university in Tokyo. These settings pass on the practical details of blanching, starter use, temperature control, and cooking in classrooms and local event spaces.
Sunki connects Kiso’s mountain setting, red turnip greens, salt-free lactic fermentation, and winter soba. From six Kiso turnip lines to a warm vessel of fermenting greens, and from a small serving of pickle to sunki soba, it remains a winter taste built from vegetable leaves, acidity, starter, and shared technique.
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Where this product is officially registered, designated, or recognized in Japan.
Geographical Indication (GI)
Registered under Japan's Geographical Indication Protection System, run by the Ministry of Agriculture, Forestry and Fisheries.
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It is written as すんき in Japanese. Search Rakuten and other Japanese sites with that spelling — the English name will not bring up the listings.
Sunki is a salt-free, lactic-fermented pickle traditionally made in Nagano's Kiso region using red turnip greens. Because the mountain valley lies far from the sea, salt was historically hard to obtain, which led to fermenting the greens for sourness instead of salting them. The pickle draws on local Kiso turnip varieties, including Kaida, Otaki, Kurose, Yoshino, Ashijima, and Hosojima turnips.
Sunki is also called sunki-zuke, referring to the same pickle. Sunki is made without salt, and is also described as using no vinegar or soy sauce. The name sunki is tied to turnip greens grown in the Kiso region and to production carried out within the Kiso region. Production involves washing and cutting the turnip greens, blanching them, layering them with sunki starter, adding warm liquid, and fermenting in a warm place.
Sunki is typically made from late autumn into winter and is usually eaten as is once ready. Sunki is also added to hot soba noodles, with sunki soba and toji soba regarded as a winter tradition in the Kiso Valley. Because its sourness comes from salt-free lactic fermentation rather than salting, sunki has a flavor different from typical pickles, and it has recently been incorporated into western-style dishes as well.
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