Discover the Benefits of Koji for Healthy Meals

Located almost exactly halfway between Osaka and Kobe, Hyogo’s Nishinomiya is a popular city, always appearing on yearly lists of the most desirable places to live in the country. W Brothers, as its name suggests, is a restaurant started by two brothers along National Route 2 near the JR Nishinomiya train station. The restaurant’s origin traces back to the older brother, Watanabe Hiroshi, getting interested in fermentation and becoming engrossed in creating recipes using koji rice malt. In addition to coming up with the dishes served at W Brothers, he has expanded into many other fields, including developing an original line of spices and other seasonings and sharing recipes online. His overarching dream, however, is to communicate and share the benefits of koji from Nishinomiya to the world.

W Brothers began by chance, after a supplier introduced the brothers to koji

W Brothers is a restaurant where you can enjoy hearty dishes, sweets, and drinks made using koji. It offers a wide variety of all-day lunch specials, featuring weekly side dishes and sauces you can choose from. The menu contains so many dishes, you’ll want to return every day. During cafe hours, it serves homemade sweets and koji-based drinks. The restaurant is particularly busy at lunch time, as it is located in a convenient spot in central Nishinomiya, a city that attracts many families.

“We started W Brothers in September 2020,” says Hiroshi. “Our first place was tiny, and we mainly focused on take-outs and deliveries within Nishinomiya. We found our present spot just as my brother and I began talking about how we really wanted a sit-down restaurant. Now, two years since relocating, I feel we’ve finally become an established place in the local community.”

The older of the two brothers that opened W Brothers, Hiroshi, had previously studied abroad and worked his way up in an Italian cafe, building a career in a world far removed from the world of koji.

“After gaining experience at the Italian place, I worked at a Japanese-style bar that catered to inbound tourists and served Hakkaisan saké. Hakkaisan’s supplier told me that besides saké, they had this other product too. The other product turned out to be Hakkaisan Koji Nama, the fresh koji that we still use in our restaurant today. At the time, we only used it sparingly in some menu items like deep-fried chicken. But then the pandemic hit, and the bar closed. My younger brother also worked there, and after talking about what to do next, we decided to try our luck in Nishinomiya and open a restaurant here. It took us a while to come up with a concept for the restaurant, but we eventually agreed on the idea of a restaurant where people can enjoy healthy foods. That’s how we arrived at our current style, developing dishes made with koji.”

Choosing the right koji involved a lot of trial and error, but we eventually settled on Hakkaisan Koji Nama

As the style and concept of the restaurant took shape, the brothers invested a lot of time choosing the right koji for their dishes.

“We tried out many kinds of koji besides Hakkaisan Koji Nama. But in the end, we had to admit that out of all the varieties we tested, Hakkaisan Koji Nama had the least odd tastes or odors and had no sharpness to it. It felt like the perfect fit for us. We even visited Hakkaisan’s facilities. They explained that, just like saké brewing, they thoroughly polish the rice before inoculating it with koji mold, which creates the Hakkaisan Koji Nama flavor. We use fresh koji to make seasonings and to complete our dishes. We want everyone, regardless of age or gender, to enjoy our food while improving their gut health and becoming beautiful from the inside out. That’s the vision behind W Brothers.”

The dishes served at W Brothers follow the concept of food that is kind of good for you. While featuring koji in everything from the mains and side dishes to the salad dressings and sauces, the menu is designed to be “just right”, with a selection of dishes that aren’t too fussy or complicated.

“Although koji has been used in Japan for ages, it’s still very strongly associated with health food. And when customers hear ‘health food’, their preconceptions inevitably perk up. This is why we deliberately went with the concept of food that’s kind of good for you, rather than emphasizing the health factor. We did this because we want more people to understand the versatility of koji and the wide range of dishes it can create. A surprising number of people don’t know the differences in using salted koji versus soy sauce koji. Most people only know that coating meat or fish with koji before grilling adds more flavor. With our current lunch specials, we try to demonstrate that koji can be used in soups, salads, and many other dishes and that it makes them taste even more delicious.”

W Brothers serves seven different lunch specials, available all day. One example is the Grilled Chicken Marinated in Koji. This hearty special lets you choose from two sauces and enjoy small side dishes, a soup, and plenty of vegetables all on one plate. Koji is used in every menu item, and the small side dishes change every week. Another attraction is the ability to recreate the dishes at home, as the restaurant publishes recipes for some menu items on its official website.

“The recipes we publish use our original seasonings like soy sauce koji and umami salted koji. Anyone can easily recreate the recipes if they use the same ingredients. Because of our experience working in an Italian restaurant, W Brothers has a very diverse menu with a blending of Japanese and Western cuisines. For simple dishes, just drizzling a seasoning over pasta will give a flavor boost. You can use them on anything.”

Koji regulates your body from within: The physical changes Watanabe personally experienced

Watanabe eats dishes made with koji on a daily basis. Since adopting this diet, he’s noticed changes in his physical condition.

“I’ve definitely seen improvements in my own physical condition. We serve the lunch specials with a sweet koji smoothie in a shot glass. I drink these smoothies myself every day, and I feel I get sick less often and my digestion has improved. Since it’s part of my daily routine, it’s not like the changes are dramatic. But I do notice many little changes in my everyday life. We also hear from customers who love the seasonings and dressings we sell at the restaurant, saying things like, ‘I don’t catch colds anymore.’ Even sumo wrestlers and other athletes drink our smoothies. We get comments from them like, ‘Drinking your smoothies boosts my energy’ and ‘I win more often when I drink your smoothies’. (laughs)”

The ultimate goal is to have an overseas showroom store

The W Brothers’ lunch specials let you enjoy a wide range of tastes. Another of the restaurant’s attractions is using its original koji seasonings and spices in many kinds of cooking at home.

“Currently, the restaurant sells our line of all-purpose Korekake Spices with Koji Powder. In addition to plain, curry, and chili flavors, we occasionally offer limited-time flavors. For today’s special, I recommend sprinkling your favorite spice over the sweet potato salad. Low-Salt Umami Salted Koji, for example, is an unheated seasoning made with just fresh rice koji, salt, and water and fermented at a low temperature. Not only is it packed with enzymes, it has less salt than commercial products, which means meat marinated in the seasoning won’t burn easily when grilled. You can use it in dressings as well as on meat or fish. We are working on developing smoothie mixes along with more original seasonings such as All-Purpose Soy Sauce Koji and Fresh Sweet Koji.”

Koji mold (aspergillus fungi), Japan’s national fungus, is gaining attention around the world. One of Watanabe’s dreams is to further promote the benefits of koji mold worldwide.

“My ultimate goal is to have an overseas showroom store. I’ve always liked other countries, and I’d really like to promote our seasonings in markets abroad. I want people not just across Japan but also around the world to understand the benefits of koji, Japan’s national fungus, as well as to know about W Brothers. We converted the second floor of our restaurant into a central kitchen, where we are now focusing on product development. The unheated koji seasonings we use in our restaurant have a short shelf life because the fermentation continues. The appeal of our all-purpose Korekake Spices with Koji Powder are their portability and ease of use. I hope people will discover the attractions of using koji while camping or out and about. We’re still in the very early stages, but Korekake Spices with Koji Powder are now available in the U.S., Canada, Sweden, Norway, and China.”

The W Brothers’ all-purpose Korekake Spices with Koji Powder uses Marukome’s Plus Salted Koji Powder

“While developing our powdered seasonings, I happened to come across Plus Salted Koji Powder. We insist on using only additive-free ingredients in keeping with the fresh salted koji powder. This is why, by just adding our Korekake Spices, meat becomes tenderer and gains a richer taste and deeper umami. We began making seasonings as a business after moving to our current location. These seasonings are now loved by many of our customers concerned about their kids’ diets or managing their own health.”

Setting out on a new path: The second chapter of W Brothers

W Brothers was started by Watanabe Hiroshi and his younger brother Shunji. Hiroshi currently is the central figure running the restaurant. He is also focused on expanding the business, such as producing seasonings with koji and developing recipes.

“My brother has recently started farming in Nagano, where his wife is from. My parents also have a plot of land, so most of the vegetables we use in the restaurant are grown by my parents. The rest are sourced from local markets. In the future, I hope to make use of the vegetables cultivated by my brother in Nagano as well. On our website, we share recipes anyone can make, while in the restaurant, we aim to offer dishes with flavors you can only experience here using slightly unusual ingredients. We organized a workshop on making okara [tofu refuse] miso a while back. If the timing works out, I’d like to plan more events like that again.”