Natto 101: Everything You Need to Know About Japan's Nutritional Powerhouse

Natto may be something of an acquired taste, but there’s no denying its countless health benefits. Packed with nutrients, this traditional Japanese superfood is one of the most popular breakfast meals in the country, despite its polarizing taste and smell. Let’s dive into all of the true facts about natto and how you can use it in your kitchen. 

Introduction to Natto

The Japanese diet is one of the healthiest in the world, thanks to its nutritious dishes and good culinary practices. One of the core principles in Japan’s food culture is that breakfast is the most important meal of the day. Hence, most Japanese people love to start their day with a healthy and nutritious meal like natto. Some eat it alone or as part of a multi-course breakfast. Before we dive into all of the characteristics and uses of this superfood, we need to start with the basics. So, what is natto food?

Natto is a traditional Japanese food made from cooked soybeans that have been fermented with a bacteria known as Bacillus subtilis. It has a mucus-like, stringy, and sticky texture with a strong pungent smell that many liken to ammonia.

Because of its slimy consistency and unpleasant smell, some people don’t like natto very much. Nevertheless, it remains a popular meal in Japan, especially in eastern regions like Kanto, Hokkaido, and Tohoku. Even those who didn’t fancy its taste and smell at first have grown to love the dish and its numerous health benefits.

Natto is typically served with rice. It may also be served alongside soy sauce, karashi mustard, raw egg, and onion.

The History of Natto

There seems to be some uncertainty regarding the origin of natto, which is common when a dish has existed for so many centuries. Of the multiple theories related to natto’s history, the story of samurai Minamoto no Yoshiie is the most popular. According to it, sometime in the 11th century (1086-1088), the samurai’s troops were ambushed in northeastern Japan while boiling soybeans to make horse food. They fled with their belongings, including the soybeans. Some days later, they opened their bags to discover that the soybeans had fermented. Minamoto no Yoshiie and his troops ate it and liked the taste.

Another origin story claims that in the 7th century, Prince Shotoku accidentally invented natto when he wrapped leftover soybeans in straw bags. People who ate the fermented soybeans liked the taste and the food gained popularity throughout Japan. The word natto is a derivative of the Japanese term for “offering place,” which is related to the kitchens of Buddhist temples. Seeing that Prince Shotoku was a devoted Buddhist scholar, it isn’t far-fetched to think that there is some truth to this origin story.

There are some who believe that natto is an evolved version of a Chinese fermented soybean meal known as douchi. It arrived in Japan from China in the Yayoi period (300 BC–250 AD).

People also say natto came from Ibaraki Prefecture, located in Honshu, Japan. Regardless of how natto was created in Japan, it became a staple in Japanese cuisine during the Edo period (1603-1868). Since then, the dish has only grown in popularity.

What Makes Natto Unique

Japan is home to all kinds of fermented soybean dishes, including miso, soy sauce, natto, and tofu. However, natto has a distinctive sticky texture and flavor thanks to the special fermentation process the soybeans undergo. The procedure also allows the soybeans to retain their shape, unlike many other fermented foods.

During the process, hydrated soybeans (natto beans, specifically) are steamed for several hours before they’re mixed with natto-kin (Bacillus subtilis) bacteria. In English, the bacteria is also called grass or hay bacillus. The fermentation process is allowed to carry on for as long as 24 hours, after which the soybeans are removed and placed in a refrigerator for a week. 

Debunking Myths About Natto

In this section, we’ll be addressing common misconceptions and myths surrounding natto by presenting factual information to clarify these misunderstandings. Here are the facts about the soybean food:

• Natto does NOT have a strong pungent taste: The food doesn't taste nearly as bad as it smells. In fact, one could say it tastes mildly bitter at worst and cheesy at best.

• Natto is enjoyed in countries outside of Japan: Despite its polarizing nature, people outside of Japan love natto too. You can find them enjoying it in China, Thailand, Myanmar, South Korea, and Nepal.

• Natto smells just as bad to people who love it: There are people who eat natto every day but dislike the smell. Many of them dislike the natto taste too. However, they eat it mainly because of its health benefits.

• Natto can be eaten as a dessert: It’s not just a breakfast food. It can serve as an ingredient for desserts like gelato or lunch and dinner foods such as pizza and pasta.

Exploring the Science Behind Natto's Fermentation

The fermentation process of many other soy products requires complex actions from multiple microorganisms. However, natto’s fermentation only needs one type of bacterium, Bacillus subtilis. The bacteria grow, create spores, and multiply on the natto beans. They also have a distinct feature that makes them perfect for the process, which is the secretion of extracellular enzymes such as amylase, levansucrase, phytase, protease, and gamma-glutamyl transpeptidase (GGTP).

These enzymes are responsible for the production of the sticky mucus surrounding the soybeans and the distinctive, strong smell and flavor. The fermentation process also makes it easier for our bodies to absorb natto’s healthy nutrients.

Health Benefits of Natto

Natto is a highly nutritious food famous for its many health benefits. Combined with other superfoods, this fermented food is one of the reasons Japan has arguably the best diet in the world, as proven by the country’s low mortality rate. The following is a list showcasing natto’s nutritional value:

• Protein

• Carbohydrates

• Calcium

• Vitamin K

• Vitamin C

• Manganese

• Iron

• Copper

• Potassium

• Zinc

By fermenting soybeans, the amount of probiotics increases, making it easier for the body to absorb the above nutrients. The presence of calcium and vitamin K2 aids stronger bone formation and lowers the risk of heart disease. Natto also has high fiber content, which aids in lowering cholesterol levels in the blood and promoting weight loss. And thanks to all of the minerals mentioned above, eating natto could greatly boost your immune system.

Different Ways to Enjoy Natto

The traditional way to eat natto is to serve it cold on top of rice (natto gohan) with a mix of soy sauce, onion, mustard, ginger, kimchi, mayonnaise, raw eggs, seaweed, mushrooms, and other ingredients. But that’s just one way to enjoy the dish. The following is a list of more ways to consume natto:

• Alongside sushi rolls (natto maki)

• Mixed with pasta

• On top of cold noodles, especially udon

• Mixed with tofu

• Alongside curry

• Mixed in salads

• On top of cheese toast

• With miso soup

• As an ingredient in desserts such as gelato, cakes, and custard pudding

• As dried or fried natto, which is not as smelly

Regional Variations of Natto

Certain regions in Japan have their own versions of natto. The following are the most popular regional variations of natto:

• Hatahata natto (Tohoku region): It contains hatahata fish eggs, which is a local delicacy in the area.

• Miso natto (Nagoya): This umami-packed variant contains a mixture of miso paste and fermented soybeans.

• Kurozu natto (Kyushu): Black vinegar is added during the fermentation process. The result is a tangy, refreshing version of the typical natto.

• Shoboro natto (Ibaraki Prefecture): This is a natto dish mixed with dried daikon radish. The process adds a crispy texture and umami taste to the natto.

• Rafute-natto (Okinawa Prefecture): This is a natto dish with pork belly and spring onions.

Natto in Japanese Culture

Natto is one of the most common traditional Japanese breakfast dishes, particularly among people from the eastern and northern regions of the country. They love to eat it with rice before they leave the house for work. Some people also buy it at eateries, supermarkets, and convenience stores. Overall, natto greatly contributes to the healthy food culture in Japan by finding its way into both traditional and contemporary cuisine.

Conclusion:

Natto appeals to not just lovers of traditional dishes in Japan but also health-conscious eaters worldwide. If you can get past the funky odor, you can easily enjoy this meal in a variety of ways. We encourage anyone looking for new healthy superfoods in their diet to try this unique component of Japan's culinary heritage.

Feel free to explore the food scene in Japan by tasting the local snacks and sweets without having to leave your house. Get a Bokksu Snack Box Subscription and we’ll send you a box of these treats every month.