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This Father and Son Innovate Traditional Japanese Sake Making

Keisuke and Rui Izumi are brewers at Manaturu Brewery, a 270-year-old brewery located in Echizen Ono, the “Little Kyoto” of Fukui Prefecture. Its location is famous for its crystal-clear water and snowy winters, two elements that allow making excellent sake. 

Manaturu Brewery takes pride in doing most of the sake-making process by hand. But do not think they reject modernity: on the contrary, the brewery has found its own way to bring innovation to a traditional industry in which pre-fixed notions usually hardly change.

Keisuke, the father, has studied fermentation, brewing, and microbiology. He has been the master brewer at Manaturu Brewery for more than 30 years. The first ginjo-shu sake he made as a master brewer won the highest score at a prefectural sake tasting. Since then, he has kept winning numerous prizes.

Rui, the son, is 27 years old. After graduating from Tokyo University of Agriculture, he went to Vancouver, Canada, and New York, USA to learn the English language and expand his knowledge. He visited local sake breweries, Japanese restaurants, and sake bars to learn about sake on the global scale. In 2018, he joined Manaturu Brewery and became production manager in 2020. The same year, he was awarded an honorable mention at the Kanazawa Regional Taxation Bureau’s Sake Competition.

In this interview, they explain the sake-making process, how they express the identity of their brewery through their sake, their way of innovating in a traditional industry, and talk about sake globalization. 

Note: In Japanese, the correct term for sake is “nihonshu.” However, by convention, I will use the word “sake” in this article.

How Do You Make Sake?

Could you please explain the process of making sake?

Rui: There are seven steps in the process. The first step is “seimai,” polishing the rice. By the way, the rice for making sake is different from the rice people eat every day: the grains are bigger and contain a lot of proteins.

The second step is “senmai,” washing the rice. It removes the bran and impurities of the rice. We soak the rice so that it absorbs just the right amount of water.

The third step is “mushimai,” steaming the rice, during which the starch quality of the rice changes. These first three steps take just one day.

The fourth step is “kojizukuri,” turning the rice into koji rice [a type of fermented rice]. We sprinkle koji starter [something similar to yeast] on the rice. This takes about two days.

The fifth step is “shubozukuri.” “Shubo” is a term that refers to yeast cultivated in large quantities. We mix the rice with water, koji, yeast, and lactic acid bacteria. This takes about 10 days.

The sixth step is “moromizukuri.” We mix shubo with koji rice, some more steamed rice, and water. Then, we let the fermentation process happen for about a month. That is what will be turned into sake.

The last step is squeezing the rice to take the sake out of it.

What is the role of the toji, and what are his responsibilities?

Keisuke: The toji is the person with the highest responsibility of the sake brewery. From manufacturing sake to managing the resources, the toji is responsible for every aspect of making sake. He also prepares the next generation of sake makers by gathering employees and teaching them the techniques. In English, “toji” is translated as “master brewer.”

Keisuke is checking rice that he carefully holds in both hands
Keisuke Izumi is the toji or master brewer of Manaturu Brewery.

For you, what are the specificities and beauties of sake?

Keisuke: Sake can be acquired in many different varieties depending on the production area, the production techniques, the type of rice, the water, and the yeast. 

Its making process is complicated, and every brewery has its own take and ways to do it. So, the properties of the sake depend on the region where it is produced and on the people who make it. To me, the fact that there are so many varieties is one of the beauties of sake.

Also, sake is made of rice, and just like the rice that we eat, it can match almost any kind of dish. You can drink it with a large variety of foods. 

To me, sake is the local culture itself. By drinking it, you can connect directly with where it was produced.

I would like to add that sake is a kind of alcohol that you can drink at different temperatures, cold or warm. Apart from sake, there are not so many kinds of alcohol that you can warm up and drink. This is another of its charms.

Finally, sake reflects the character of each region of Japan. It has been produced for many years under the influence of Japan’s climate and natural features, traditions and culture, and regional food and ingredients. To me, sake is the local culture itself. By drinking it, you can connect directly with where it was produced.

Expressing the Identity of the Brewery

What do you want to convey through the sake you make?

Keisuke: We are a small brewery, we do almost everything by hand, and we have our own way to do certain things. There are a lot of sake breweries in Japan, but we are trying not to be like the others, and to protect our personality. We are doing our best to make sake that only we can make, with the qualities that only we have.

Keiseuke is using a wooden stick to mix the contents of a barrel
At Manaturu Brewery, many steps of the making process are done by hand.

You make sake by hand as much as you can, without relying too much on machines. Why is that? 

Keisuke: Machines are very reliable, and it is almost impossible to make mistakes with them. However, they can only produce until a certain level of quality. I believe that making sake by hand is important, even necessary if you want to enhance the quality of your product: that is how you express the identity of your brewery and the personality of the brewers.

What is the most important thing in making good sake?

Keisuke: As I mentioned earlier, the sake-making process is complicated. There are a lot of factors such as the sake rice, the water, the climate and natural elements, the brewer’s talent, etc. However, all of them are necessary, and it is hard to tell which one is more important than the others. 

In Japanese, we have a phrase, “wajoryoshu” [和醸良酒], which means that you can make good sake if you can maintain harmony. So, I think the most important thing is that all the brewery members are in harmony and aim for the same objective, to be a team that makes good sake.

So, it is more about the spirit of the brewery than about tangible objects?

Keisuke: Yes! It is important that each member seeks harmony in the brewery, especially because there is a lot of group work, and it is a long manufacturing process.

Innovating a Long Sake Tradition

A traditional Japanese building under the snow
Manaturu Brewery under the snow

Your brewery is ancient and dates to the Edo period (16031867). How does it feel to have such a legacy? 

Keisuke: If I had to put it in one word, I would say it is our pride. The brewery was created in 1751 and celebrates its 270th anniversary this year. Actually, the Edo period started 268 years ago, so our brewery is even a little older than that. 

Our brewery has its own history. Along this history, many people have devoted themselves to making sake. I feel very proud to be one of the members of this long history, and I hope we can keep this legacy alive for a long time.

Are there times when this long history can feel like pressure?

Keisuke: For me, not so much! [laughs] What about you, Rui?

Rui: Not really. [He pauses and thinks for a few seconds] More than feeling pressured, I feel excited about doing things the way I want, and about the idea that our sake will be available to more and more people in the world.

It is important to not be afraid of changing the state of things, to not be too attached to pre-established rules.

You keep the traditions alive and make classic sake, but you also make new and original sake such as sake that has a fruity, apple-like flavor, sake to mix with carbonated drinks, sake aged in a sherry barrel, etc. Where do you find the inspiration for these new ideas? 

Keisuke: I make sure to always be looking at many things, and to look for new perspectives. I go to new places, make new experiences. All of these experiences accumulate inside me and prove to be useful later on.

In one of his speeches, Steve Jobs talked about connecting the dots. Each experience taken separately may not look relevant at first. It is only later, when connected with something else, that it allows giving birth to something new. That is when you make new discoveries.

I believe it is also very important to trust your own sensibility and follow through with your ideas. It is important to not be afraid of changing the state of things, to not be too attached to pre-established rules. It is also important to not care too much about what other people think, or what they will tell you if you do this or that.  

In traditional Japanese industries, there is a tendency to believe that protecting the traditions is “good,” and changing anything is “bad.” In Japanese, we have the word “densho” [伝承], which means transmitting traditions without changing a single thing.

However, I believe that “tradition” is about adding innovation to elements that have been protected for many years, so that it fits new times, and can be loved by people for as long as possible. That is why for me, “tradition” is about taking up new challenges and creating new products.

Aiming for the Same Ideal as Father and Son

Rui is in the process of sticking a label on abottle
Rui wants to challenge the fixed concepts regarding what a sake bottle label should look like.

What is the ideal sake you are aiming for? 

Rui: We would like to make a sake that is a subtle, delicate, and profound traditional sake, while at the same time, appealing to people who are usually not so interested in sake.

I think that there are fixed, rigid concepts about what traditional sake, or sake, should be in general. We hope to make sake that is not about past culture but reflects the actual culture, and that will last for a long time too.  

Are there other original kinds of sake you are planning to make? 

Rui: Now, we are thinking about bringing something new, but not only within the contents of the sake. Nowadays, it is considered “normal” for sake to be delicious, and there are more and more varieties.

However, I have always found it strange that the sake visuals, such as the bottles’ labels, do not reflect what their content tastes like. That is why our sake that tastes fruity like apples has a cute apple design. By expressing what it tastes like on the label, people who do not know much about sake or have not tried many sorts of sake so far, can easily choose a type of sake that will fit their preferences. We want to keep doing this for other products.

Regarding the label for the sake ‘Rui,’ people who like sake might say things like, ‘That is not what sake should look like,’ but my father immediately said, ‘Isn’t that good?’

You seem to get along very well. Do conceptual fights between father and son sometimes happen during the sake-making process?

Keisuke: My son has started making sake only recently. For now, he is learning the process, but maybe fights will start happening when he starts wanting to do his own thing. [laughs] What do you think?

Rui: Well, I am only at the stage where I am taught everything, so I have no clear opinion yet about the way to make sake.

Regarding the label for the sake “Rui,” people who like sake might say things like. “That is not what sake should look like”, but my father immediately said, “Isn’t that good?” [Both laugh] We have the same point of view on these kinds of ideas.

What are your personal favorite sakes among the different sorts you are making?

Keisuke: My favorite sake is called Sow, which is refreshing with a little citric acidity. It is made with a white koji starter made from shochu, which is something other master brewers had almost never tried. It received great appreciation both inside and outside Japan, and since it is a little acidic, it matches well with Western food as well as Japanese food.

Rui: For me, it is the daiginjoRui” [laughs]. It is the one with the cute apple label. It includes a lot of components that give it an apple-like flavor. It is the first sake for which I tried to express the taste of the content on the label. It pairs well with white fish and sashimi.

Offering Sake to the Rest of the World

Rui, you have studied in Canada and America, where you have worked in Japanese restaurants and sake bars. What did you notice about the locals’ approach to Japanese sake?

Rui: I have worked in Japanese restaurants and also at an oyster bar. They had many sorts of sake on the menu, and I noticed how important pairing sake with food was. It deepened my view on the relationship between sake and food.

I also realized that people see sake as something to drink only with Japanese food. I think that it is very important from now on to also make sake that will match well with all sorts of cuisines from around the world.

Keisuke and Rui are serving sake for clients to taste
Keisuke and Rui appreciate getting direct feedback from their customers.

You export your sake to the US and several Asian countries. What do you think is necessary for sake to expand into the world? 

Keisuke: As Rui explained earlier, it seems that in other countries, sake is still perceived as something to be consumed only in Japanese restaurants, with Japanese cuisine. I believe that sake globalization will only happen when people start drinking sake with cuisine from their own countries. 

Earlier, I mentioned that sake can match any kind of food. However, sake usually does not pair well with oily food and spicy food. So, we want to do our best to make sake that can be appreciated in any place in the world, in any climate and cultural setting, with any kind of food.

What are the next global-scale challenges you would like to undertake?

Keisuke: Since we are not present in the European market, we would like to try to export our sake there. Also, we would like to do more research about our customers in the countries where our sake is available. We would love to know what the local people like and do not like about our sake, hear their suggestions, and more. So, we would like to do some research and create sake that would match the preferences of our customers from other countries. 

What Is Tradition?

As a Kokoro writer, I have met many people in Japan who are guardians of either gradually misunderstood or even slowly disappearing traditions. Most of the time, these people are looking for new ways to educate the world about what they do. For example, artist Allan West has turned his atelier into a live display for Japanese painting, and Shinto priest Soushi has started a parallel career as a pop singer.

Depending on their activities, these new takes can be more or less well received by their own fields. In the traditional and—let us say it—a little rigid industry of Japanese sake, there must be voices criticizing Manaturu Brewery’s new projects and ideas. Hence Keisuke Izumi’s advice to not pay too much attention to what other people think.

Should tradition be immutable? Should the past influence the present so much to slow the disappearance of traditions? Some people may answer yes to these questions; however, I believe that Manaturu Brewery’s philosophy makes a lot of sense. Traditions exist to be loved and appreciated by people for as long as possible, and innovations can help them stay relevant through the test of time. 

The challenge resides in innovating just the right amount and the right way so that it does not denature the original spirit of the tradition. In my opinion, Manaturu Brewery achieves a great balance by keeping their sake-making process done by hand, while not being afraid to create new sake and new visuals for the joy of all people. They are able to do so because they know where their identity and their values reside. 

I hope that more people will get to know about their philosophy, and that it can inspire Japanese industries of all kinds.


Born in France, I've been living in Japan since 2011. I'm curious about everything, and living in Japan has allowed me to expand my vision of the world through a broad range of new activities, experiences, and encounters. As a writer, what I love most is listening to people's personal stories and share them with our readers.

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