Natto of the Future! SOYFFEE Mixes Japan’s Famous Fermented Soybeans With Coffee

“Natto,” a fermented soybean delicacy from Japan, has been making a splash on the global health food scene owing to its high nutritional value. However, its potent aromas put many off, robbing them of the benefits of this remarkable superfood. Shonan Soy Studio, a natto producer on the coast of Sagami Bay in Kanagawa, aims to rectify this by mixing natto with coffee to create a treat all can enjoy. The resulting SOYFFEE pairs the nutrition of natto with the alluring fragrance of coffee, making it a great starting point to enhance your diet without suffering through the smell.

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Natto: The Japanese Superfood With a Long History

Natto is one of Japan’s many fermented soybean products, with a history supposedly stretching back to the Yayoi Period (300 – 250 BC). While the country may have changed over the millennia, the love for natto remains the same.

The production of natto is very simple: dried soybeans are soaked and boiled in water before natto bacteria, often found in rice straw, is added and left to ferment. The resulting natto has a sticky, stringy texture and distinct aroma, with significantly more protein, vitamin B complex, zinc, and fiber than rival soybean products. Eating natto also increases the good bacteria in your gut, improving intestinal health. Owing to these benefits, natto is often dubbed a “superfood.”

SOYFFEE: Soybeans and Coffee For the Natto of the Future

The basic idea behind SOYFFEE was to create coffee-esque natto. On the surface, it looks like your typical natto, only with the smell replaced by the mild fragrance of coffee. While the aromas have changed, SOYFFEE still retains the soft texture of natto, although it isn’t as sticky as the regular variety.

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Crafted With Care From Ingredients to Packaging

SOYFFEE is available in several different flavors and forms. Complementing the “Original” coffee natto is the “Original-Double” with twice as much coffee, along with the sweet “Original-Honey,” “Roasted,” which pairs well with dried fruits and candy, and “Powder,” made from crushed low-temperature roasted soybeans.

Being sticky, dry, or powdered, SOYFFEE goes with virtually any dish. From bread to salad, dessert, yogurt, curry, or pasta, a dash will elevate food to new heights. And because the main ingredient is soy, it is 100% vegetarian and vegan. Products can be purchased online or in-person at the Shonan Soy Studio showroom.

*Details about purchasing SOYFFEE can be found at the bottom of this article.

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We Asked Our International Staff What They Think About SOYFFEE

As mentioned, there are many varieties of SOYFFEE and numerous ways of enjoying it. Our international editorial staff purchased the “Original-Double” and “Roasted Chocolate Block” to see if it really lives up to the hype.

Apparently, the extra-coffee “Original-Double” goes down a treat on toast or with fresh cream, so we opted for toast with cream cheese. The sticky natto paired perfectly with the soft, rich cream, while the coffee adroitly masked the strong aromas as advertised. Soft, delicate, and slightly sweet, SOYFFEE toast would make for a great pick-me-up between meals. However, we found that the trademark stickiness of natto somewhat remained, so those put off by the texture of regular natto may still find this a tough sell.

“Roasted Chocolate Block” is made in collaboration with Dari K, a Kyoto chocolatier with a focus on sustainability. It’s made from coffee natto covered in 78% cocoa chocolate from Indonesian cocoa beans, and is 100% vegetarian and packed with protein and natto bacteria. The crunchy natto and bittersweet chocolate forms a symphony of contrasting flavors. While best paired with strong coffee or wine, we sampled it with sour yogurt and orange, which yielded a heavenly mouthfeel.

SOY BREWERY: A Takeout Cafe With Sustainable Fast Food

Keita Onooka, the creator of SOYFFEE, is forever coming up with new ideas and businesses. In April 2022, he opened SOY BREWERY, a takeout cafe in Chigasaki specializing in fermented foods and soy-based products.

SOY BREWERY serves plant-based dishes designed around the ideas of “healthy eating,” “sustainability,” and “art.” Most of the ingredients come from Shonan Soy Studio, the producers of SOYFFEE, arranged into preservative-free natto products with miso, edamame beans, soy “meat,” and more.

Browsing the menu, the “Miso Latte” catches our eye. This intricate drink is made from  a broth of kelp and bonito flakes mixed with white miso and aged brown miso, finished off with soy milk to create a savory drink like you’ve never had before.

We also couldn’t resist the three types of burritos: Teriyaki-Mayo, Taco, and “Buddha,” all made from soy meat, powdered natto, fresh vegetables, genmai brown rice and koji malted rice from Shonan, and other natural ingredients. The tacos were refreshing, healthy, and satisfyingly filling. All the menu items are well priced, and available for take out. You can also purchase “Powder” SOYFFEE here too.

SOY BREWERY also does its part to protect the environment by not using any plastic wares and encouraging customers to bring their own cups. Opening at 8 am and within walking distance of the beach, the cafe has become a hit with local surfers looking to grab a nutritious breakfast before hitting the waves.

Shonan Soy Studio: Redefining Japan’s Traditional Dishes

Sitting within the town of Oiso in Naka District, Kanagawa Prefecture, Shonan Soy Studio (est. 2019) consists of a natto factory and tasting room. Their mission is to make Japan’s traditional soy dishes into a worldwide sensation while discovering new ways of enjoying them.

Shonan Soy Studio is housed within a remodeled traditional Japanese homestead right by the Oiso coastline. The distinctive original roof tiles remain, while the walls have been painted white to contrast with the dark “noren” curtain by the entrance. The 1st floor veranda is lined with cushions inviting patrons to sit and relax, making them feel as if they were visiting a friend’s home, rather than a shop.

Promoting Healthy Eating With Natto

Keita started his business with the desire to "promote the importance of healthy eating while making natto more accessible to the world.”

During his time studying abroad, he encouraged his international friends to try natto. However, many of them couldn’t get over the smell, often comparing it to "three-day-old socks.” Spurred on by these words, Keita spent two years developing a way to suppress the smell through trial and error. Ultimately, he discovered that coffee worked the best.

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Natto: More Than Just a Health Food

Everything that Keita does, from the coffee-flavored SOYFFEE to the healthy fast food at SOY BREWERY, reflects his desire to "promote traditional Japanese food” here and abroad. He hopes to improve the health of people all over the world by introducing them to a new diet based on fermented soy products.

During his travels through developing countries, Keita became painfully aware of the disparities in how people lived. In contrast, life in Japan is remarkably convenient - you can go where you want, and eat as you like. If you have a dream, there are numerous ways to work towards making it a reality. However, not all people have this luxury. If you travel to, say, rural Laos, one of the poorest countries in Southeast Asia in terms of GDP, you will find children suffering from severe protein deficiencies and more.

That’s why Keita adopted "BITE for BITE” as the philosophy behind Shonan Soy Studio, using parts of his proceeds to purchase and donate soybeans to Laos, while organizing Laos coffee tasting events at his store.

The company also collaborates with local school cafeterias in the Shonan area, providing nutritional soybean supplements to children in need. This is part of Keita’s quest to correct the disparities stemming from birthplace and environment, both in and outside Japan.

The One and Only Coffee Natto

You can buy SOYFFEE products in-person at Shonan Soy Studio, or online through their official website. With a sizable assortment to choose from, you can easily find something that suits your palate. Who knows, maybe SOYFFEE will make a natto fan out of you after all!

For more on Keita Onooka’s story, check out the following article:

Keita Onooka - Changing the Way the World Views Natto Through Coffee

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Kanto Feature

The information in this article is accurate at the time of publication.

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About the author

Fuchi Pan
Born in Taiwan, currently living in Tokyo. Yearning for a life surrounded by handmade goods and things she loves.
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