Producer Spotlight - Kutsuma Seihun: Milling Japanese Soba

  • 5 min read

Kutsuma Seihun was established in Odawara City in Kanagawa Prefecture in 1903. Specializing insoba (buckwheat) flour milling, Kutsuma Seihun has been in business for over a century. Using their expertise in soba flour production, they offer various services for soba noodle shops, such as milling soba flour for commercial and retail use, consulting restaurants on the production of soba noodles and dipping sauces, developing products using soba flour, and sourcing other ingredients required by soba restaurants, such as oil and wheat flour. In this interview, we had a chance to speak with Mr. Kutsuma, CEO of Kutsuma Seihun.

Mr. Kutsuma spent an hour talking about the history of the company, his own career, and the appeal of soba. His passion overflows when talking about soba, making us fall in love with it even more. 


Kutsuma Seihun


In our November Kanagawa Nourishing Essentials Care Package, we will be featuring two soba specialties made from soba flour ground by Kutsuma Seihun:soba karinto (classic fried Japanese sweets food, made from flour and yeast formed into bite-sized pillows and then coated with brown sugar)andsoba okoshi (popular Japanese confectionery akin to a puffed rice treat).

Although there are many kinds of Japanese sweets made using wheat flour, there are very few made using soba flour. Kutsuma Seihun developed their soba karinto and soba okoshi as a way to introduce people to a larger variety of products made using soba flour. 


Kutsuma Seihun

soba okoshi


Surprisingly few people have ever seen soba before it is made into soba noodles.

Soba originally comes covered in a black shell and is known asgen-soba. In order to remove the shell, gen-soba is placed in a centrifugal machine. As the gen-soba spins, it hits the rubber edge of the machine, which removes the shell. Tasting it as is, soba has a delicate flavor. And since it is easily digestible, it doesn't need to be heated like other flours in order to make it edible. 

Kutsuma Seihun

Black, unpolished gen-soba and the inner white seed

Kutsuma Seihun uses two milling methods for their soba: the traditional method using a stone mortar and a machine method.


 Kutsuma Seihun
 Kutsuma Seihun
 Kutsuma Seihun
Stone mill grinding

Kutsuma Seihun mainly uses the stone-mill method to grind their soba, which requires a lot of time. However, since it doesn’t generate much heat, the soba maintains its natural flavor and aroma.


Kutsuma Seihun

Roll milling

Milling machines can be categorized by the type of soba flour they mill. By combining different soba flours, various tastes, textures, and flavors can be produced. The ability to mill flour so precisely is one of the advantages of roll milling.


 Kutsuma Seihun
 Kutsuma Seihun


Various types of soba flour produced by roll milling. Sarashina powder, which is made from only the whitest part of soba, produces pure white soba noodles.

Kutsuma Seihun

Different colors of soba flour.

Why soba?

Following World War II, Mr. Kutsuma's grandfather wanted to specialize in either wheat or soba flour. Since wheat flour production was controlled by the government, he decided to specialize in soba flour, which had more production freedom. In 1976, the company was reorganized and began handling both domestic and imported soba flour. Of the 130,000 tons of soba consumed in Japan, 100,000 tons are imported. Of the remaining 30,000 tons which is domestically produced, about 45% comes from Hokkaido, followed by Fukushima and Kagoshima. Because of how dense soba grows and its strong ability to absorb the earth's nutrients, it does not develop weeds and was historically valued during times of famine. 

Moisture levels of domestic and imported soba 

When comparing domestic and imported soba, domestic soba is superior in taste. This is due to soba’s optimal moisture levels. A highly poisonous fungus can grow on soba during transportation if moisture levels are too high. Therefore, when transporting soba, it is necessary to lower the moisture levels, which results in a bitter taste. The price of domestic soba is also three times higher than that of imported soba, and due to the small harvest, domestic soba is not widely used in conventional soba noodles. We encourage you to compare the taste if you find soba made from 100% domestic soba flour.

Hokkaido “Shosaku Soba”

Mr. Kutsuma sources his soba from Hokkaido, a region with gentle hills that are ideal for growing soba. The cost of soba was originally low given the area was more focused on a booming dairy industry. Mr. Kutsuma’s father found contract farmers from scratch, increased the harvest, and developed their own branded soba known as "Shosaku Soba" - a single origin soba produced by a local farmer,Mr Shosaku Takahashi. The quality and strength of Mr. Kutsuma's soba flour comes from the traceability back to the producers and the place of production.


Kutsuma Seihun

Mr. Kutsuma (right) with contract farmers


Soba's challenges

Soba faces two main challenges. First, it cannot self-pollinate. Insects won’t fly if it rains or is cold for a long time. If this happens, pollination will not take place, which greatly affects the growth of soba plants. Soba plants are also sensitive to wind and can’t maintain their fruits during strong winds. Just one typhoon before harvest can ruin the whole crop! The second challenge is that soba is an allergen. 

Because of these issues, national soba associations are working together on subsidized projects to create self-pollinating seeds and develop non-allergenic soba.


Kutsuma Seihun

Shosaku soba field


Which type of soba is the best?

Fromsarashina-soba(white) toinaka-soba(black), which type of soba is the best?

"That is a really difficult question. Each person's preference for soba is much different than for udon. In addition, the dipping sauces for soba vary widely in terms of whether they focus ondashi (soup stock) or soy sauce, so it is difficult to say for sure what is best for each person. When considering what kind of soba to serve at a restaurant, we consider the type of noodle, the kind of soup, and whether the soup should match the soba or the soba should match the soup - the combinations are endless. From a nutrient standpoint, the highest nutrients are found in soba noodles made fromhikigurumi soba powder, which includes soba in its entirety after the shell has been removed.” - Mr. Kutsuma

When eating soba, it is important to know not only the percentage of soba flour, but also what type of soba flour is used.


Kutsuma Seihun

Delicious tempura soba noodles made with soba flour from Kutsuma Seihun


Katsuma Seihun

Leave a comment (all fields required)

Comments will be approved before showing up.

Search our shop