Soboro Natto (also called Shoboro Natto) is a local dish of Mito City made by pickling sticky-stranded natto together with warihoshi daikon (sun-dried, split daikon radish) in a seasoned liquid. 'Shoboro' is said to be a Mito dialect pronunciation of 'soboro.' In the Edo period, Mito was known for natto-making using early-ripening small soybeans that could be harvested before typhoon season, and it was customary to distribute freshly made autumn natto among neighbors and temples. The dish is said to have originated as a way to keep leftover natto, or natto that hadn't stranded very well, edible for longer by pickling it together with dried daikon. Unlike the branded product Mito Natto, which is natto itself, Soboro Natto is a preserved food in which natto is processed more like a pickle, which is the key distinction between the two. Its appeal lies in the contrast between the crunchy texture of the dried daikon and the soft, crumbly texture of the natto, and today it is made and sold by long-established pickle shops and natto shops in Mito, enjoyed as a topping for rice, a snack with drinks, and a popular Mito souvenir.
Origin
In Edo-period Mito, natto-making thrived using early-ripening small soybeans that could be harvested before typhoon season, and it was customary to share freshly made autumn natto with neighbors and temples. The dish is said to have originated from the idea of pickling leftover natto, or natto that hadn't stranded very well, together with dried daikon so that none of it went to waste and it could be eaten over a longer period.
History
Onuki Tsukemono Shokuhin, based in Mito City, was founded in 1915 (Taisho 4), and it is said that in 1920 (Taisho 9) the company improved the originally salt-flavored soboro natto into a soy-sauce-flavored version and began selling it as a commercial product for the first time. In the mid-Showa period (around 1965-1974), the name 'Shoboro Nattozuke' was trademark-registered, and the dish became established as a signature Mito souvenir and side dish, moving beyond its origins as a homemade preserved food.
Features
The dish is characterized by chopping sun-dried warihoshi daikon and mixing it into sticky-stranded natto, then seasoning and pickling it with soy sauce, mirin, and other ingredients. Its appeal lies in the contrast between the soft, crumbly texture of the natto and the crunchy bite of the dried daikon, and because it keeps relatively well even at room temperature, it is enjoyed more as a preserved pickle than as plain natto.
Main Ingredients
Food Culture
Once made at home as a preserved food stored in earthenware jars, it has been passed down as a way to make good use of natto shared with guests or temples rather than letting it go to waste. Today it is enjoyed as a topping for rice or ochazuke and as a snack with drinks, and it is also a popular classic souvenir among visitors to Mito.
How It Differs from Home Cooking
At home, it is often prepared quickly by simply mixing chopped daikon into leftover natto, whereas specialty shops use sun-dried warihoshi daikon and slowly pickle it in their own seasoned liquid to mature, producing a product with both better keeping quality and richer flavor.
Famous Shops
大貫漬物食品
茨城県水戸市元吉田町2730-4
A long-established pickle shop founded in 1915 (Taisho 4). Sells Shoboro Nattozuke in tray packs of 6 or 12.
View details →水戸天狗納豆（株）笹沼五郎商店
茨城県水戸市三の丸3-4-30
Sells Soboro Natto, made by seasoning shredded dried daikon with a soy-sauce-based mixture and combining it with natto. Around 300g for approximately 756 yen (tax included).
View details →FAQ
Q. Which is correct, 'Soboro Natto' or 'Shoboro Natto'?
A. 'Shoboro' is said to be a Mito dialect form of 'soboro,' and locally the name 'Shoboro Natto' is also widely used. Both refer to the same dish; the spelling or trademarked name used simply varies by shop.