Nagano/Suwa "No. 7 Summit 2023"—The No. 7 Yeast Born from the Suwa Brewery, and the People and Towns It Connects Today

Brewing Society of Japan No. 7 yeast is now used in many breweries across the country. This yeast was discovered in 1946 from fermenting moromi (mash) at the Suwa brewery of Miyasaka Brewing (Masumi) in Suwa, Nagano. It was discovered by Dr. Shoichi Yamada of the National Research Institute of Brewing.

The strain, named "Brewing Society No. 7," was not kept exclusively by Masumi but was distributed nationwide, helping to build the framework for modern sake.

In other words, No. 7 is a yeast born from the land of Suwa.

There is an event held only once a year at the brewery where it originated: the "No. 7 Summit." Invited by Katsuhiko Miyasaka of Miyasaka Brewing, I traveled to Kamisuwa to attend.

■ Event Overview (*Finished)

◉ "It's not flashy"—That's why we choose No. 7

In 2019, Masumi decided to return to using its own No. 7-derived yeast strains. The shift began gradually around 2013 when Katsuhiko returned to the brewery, and today, almost all products are made using No. 7.

So, what is good about No. 7? During the event, the first thing Katsuhiko mentioned was its high degree of freedom. You can usually tell when sake is made using No. 18 or No. 19 yeast. No. 7, however, has a wide range.

A range in serving temperatures, a range as a food-pairing sake, and a range of flavors that emerge from each brewery and each brewing process. Even when breweries that used to create variety by changing yeasts consolidate to using only No. 7, they can still achieve sufficient breadth.

And one more thing.

"It's not flashy. You need something flashy once in a while, but you'd get tired of it every day, wouldn't you?"

The title of being the brewery where No. 7 originated is a selling point in itself. Knowing this, Katsuhiko does not use it as a sales pitch.

Toward the end of the event, a question that hit the core was asked from the audience. It is said that for Kumamoto's No. 9, the yeast distributed by the Brewing Society and the one cultured at the brewery are different. So, what is the situation with No. 7?

The No. 7 that Masumi uses is not the one distributed by the Brewing Society. It is a strain that has been preserved in our own brewery. We have 20 to 30 types of our own strains in-house, from which we are constantly selecting, keeping 5 or 6 on hand. Some are stored frozen, and others are not. We keep multiple strains as a form of insurance.

"It's a treasure, isn't it?"

There is no thought of selling it to other companies. However, when asked if the Brewing Society's No. 7 should spread even further in the future, he replied that it was not his place to say, and that it is up to the brewers to choose.

The brewery where it originated does not claim ownership of the yeast. The choice to open up the strain that Dr. Yamada brought back in 1946 to the whole country, and this current attitude, are likely connected.

◉ Sake brewed with the decision to "never serve it warm"

One of the guests, Kensei Yanai, is the 9th-generation owner of Toyokuni Sake Brewery in Furudono-machi, Ishikawa-gun, Fukushima Prefecture. The brand he launched himself at the end of 2010 is 'Ibuki'.

The Ibuki served on this day was 'Urayanagi,' a seasonal sake released from early summer through the summer. The green color is the brand color of Ibuki, capturing the scenery of the mountain town directly in the color of the sake. The slight touch of light blue on the label represents the murmuring of a river. It is a refreshing bottle with a lower alcohol content.

In fact, Ibuki has been using No. 7-related strains for its standard products as well. Both Fukushima's F7 and 701 are said to be strains with ties to No. 7.

For Urayanagi, because the alcohol content is lowered, they chose the authentic No. 7 rather than a mutant strain. It is because they need the strength to grow firmly within the mash without being eliminated even when blended with other yeasts.

And Mr. Yanai said this right after the second part began:

'I made this Urayanagi with the firm decision that it must never be served warm.'

He continued by saying that since he heard it was Jo-san who would be warming the sake, he had been looking forward to this day personally.

The Daiginjo that Katsuhiko-san brought was also not brewed with the intention of being served warm.

◉ Warming is cooking

Four tools were lined up in front of Jo Takasaki. A copper chirori, tin, stainless steel, and a glass beaker. He uses them differently, with the image that copper is for grilling, the beaker for steaming, tin for stewing, and stainless steel for deep-frying.

'Warming sake means applying heat. In other words, it is cooking.'

He decides the temperature at the moment the aroma settles. Depending on the sake, there are one to three such moments. The moment the aroma stops rising is the moment the flavors have blended.

On this day, Ibuki was served at 70°C and Masumi at 65°C. The temperature range also changes depending on the shape of the vessel.

I was surprised when I drank it. The contours that were present when served cold did not disappear. Instead, while the accent of the acidity became softer, only the core stood out. Both brewers were also surprised.

'Sake that is brewed with care is delicious even when warmed. Why must it be cold?'

That is what Jo-san says. It is no longer an era where sake can only be warmed if it comes from a brewery that specializes in sake for warming, as it was in the past. The brewery's technology has improved to that point. Therefore, we can trust warming more.

Katsuhiko-san's words resonated with me the most that day.

'We shouldn't force how people drink it. I realized that it is the chef and the drinker who decide how to handle the ingredients we have created.'

Yanai-san was also reflecting on his own side of things. 'Please chill it, do not warm it'—the reason he specified that was because he was afraid that if he didn't make such a suggestion, people wouldn't drink it properly. By imposing restrictions, the brewers were finding a sense of security.

For the past 30 to 40 years, sake consumption has been in continuous decline. Katsuhiko-san says that one of the reasons for this might be that they pushed the 'chill it' approach too far. You can't drink that much cold sake. Jo-san also agrees, saying that he can only drink half as much cold sake as he can warm sake.

That is certainly true. I, too, cannot go back to cold sake once I start drinking it warm. It's not just about the taste, but above all, it is easier on the body.

◉ It all started with a DM

The three people on this night were not introduced by the appropriate parties in the industry.

In the midst of the COVID-19 pandemic, Yanai-san was lost regarding the future of his brewery. What is a sake brewery? What should he do with this brewery? In 2021, he sent an email to Katsuhiko-san, whom he had never met, and came to Suwa. He says that what he gained there was not an answer, but a major hint. The way of being as a sake brewery. The relationship with the town.

The following year, in 2022, it was Katsuhiko-san's turn to visit Furudono Town.

'It was more rural than I had imagined. Continuing to brew sake there while still carrying the label of Fukushima. I think it was a significant decision for Yanai-san, who was in his 20s at the time of the disaster, to decide that he would carry this brewery on his shoulders for the next 20 or 30 years.'

Yanai-san later learned about Takasaki-san's activities. What moved Jo-san's heart was the painting that the artist collective Overalls painted on the walls of Futaba Town, Fukushima Prefecture. Futaba Art District. About 10 paintings have been created on buildings in a town where people have not returned.

Yanai-san was also moved when he saw those paintings. He sent a DM to Overalls himself and decided to have them paint a mural on the wall of the Toyokuni Sake Brewery—30 meters wide and 4 meters high. The story was that work would begin the week after the week I interviewed him.

Using the same method, Yanai-san sent a DM to one other person. It was Sato-san, who brews 'haccoba' in Odaka, Minamisoma City. This is two towns over from Futaba Town, where Jo-san was born. On this day, Sato-san was in the audience. He was suddenly called upon, stood up, and said this:

'All of our sake uses No. 7 yeast.'

They use an unprecedented brewing method where ingredients other than rice are fermented together. Even so, they choose No. 7, which has strong fermenting power, to bring out the umami of the rice.

Katsuhiko-san says that breweries with a long history have a sense of 'it must be this way.'

'If you look only at sales, the history of continuous decline is longer. It's easy to end up talking about how it's painful and how it doesn't sell, and you feel like you have to fake a happy face. But if you aren't enjoying it like they are, you won't attract companions.'

◉ Living here

At the entrance of the venue, there was a drum painted in red and yellow.

It was originally a sake barrel. The people of 'Osuwa Daiko,' who play the drums dedicated to Suwa Taisha Shrine, turned the barrels that were used to pack and sell the new sake brewed in winter into drums. On this day, I was also allowed to hear its sound. The barrel that carried the sake now makes a sound dedicated to the shrine.

During the day, Katsuhiko-san was saying this:

'We have been doing things here, and we will continue to do things here in the future. That is why this town needs to be bustling.'

Alongside improving sake quality and organizing the company, Mr. Yanai is focusing his efforts on the revitalization of the town. Mr. Jo continues his activities with thoughts of Futaba Town, which lost its shops. The earthquake and the pandemic shifted their respective outlooks on life. Beyond that, fate brought them together, and these three people are now in the same room.

It was likely a coincidence that No. 7 emerged from the mash at a Suwa brewery. However, it is no coincidence that the brewery still stands in Suwa today, carrying that coincidence with it. Yeast comes from the land. The brewery remains in that land. That is always the order of things.

◉ Reasons to go to Suwa

Kamisuwa is actually on the closer side for my business trips. It takes about two hours on the Azusa train. There is a footbath on the station platform, and hot springs bubble up throughout the town.

This gathering could not happen in Tokyo. Meaningful conversations are exchanged at a distance that doesn't feel forced. Because the management isn't uptight, the listeners don't have to be on guard either.

I only learned after arriving at the venue that this day marked the first in-person event in three years. Despite the rain, 30 people had gathered. I decided that I would go to Kamisuwa again.

No. 7 is a yeast born from the air of this land. Drinking that sake in that land—that alone changes the meaning of a glass.

Incidentally, Dr. Yamada discovered No. 7 in 1946. By 2026, when this article is published, it will have been 80 years.

▼ Instagram immediately after the visit

▼ I wrote about Takashima Castle, which I visited the next day, in a separate article