Make Your Own Natto by Fermenting Soybeans With Bacillus Subtilis on a Warmer in a Day - Easy Recipe

Japanese "natto" is a vitamin-rich, fermented superfood made from soybeans. It's a healthy probiotic that is good for your microbiome and modulates immune response, thereby reducing inflammation and allergic reactions. Beneficial to your liver and skin, it will help keep your arteries open and is especially rich in vitamin K2, which is of particular benefit to post-menopausal women who are prone to bone loss.

There's a catch, though. It's hard to find in Calgary, and when you do, it's either really expensive or dead and dry. Really, probiotics are best consumed fresh. And why should something made from soybeans be so expensive?

The bacteria that give natto all of its health benefits, Bacillus subtilis, isn't the sort of thing you can pick up at the corner store, and it's got its lifestyle preferences. B. subtilis needs to be kept warm, around 100 degrees Fahrenheit or around 40 degrees Celsius. Unless you own a Japanese warmer, a dehydrator, or an oven that will hold a temperature that low, you won't be able to keep the necessary bacterial culture going. It takes 20-24 hours of just the right amount of warmth to turn cooked soybeans into natto.

Well, my stove has a "warming" element that's supposed to keep food warm rather than cook it. I kept a pan full of water on that element near the lowest setting, and the water felt warm but not hot, so around 40 degrees Celsius. Since I also own a pressure cooker, I felt ready to try an experiment.

I ordered a natto culture starter kit containing B. subtilis from Cultures for Health (http://www.culturesforhealth.com/how-to-make-natto) and followed the basic directions. I soaked about 1 kilo of dry soybeans in cool water for about 4 hours, then cooked the beans in a pressure cooker for about 30 minutes. I transferred the cooked beans to a sterile pot (made sterile by baking it dry in an oven for 20 minutes). Once the beans had cooled to about 40 degrees, I put them on the warmer, sprinkled a little of the natto starter culture on the top, then mixed things up with a sterile spoon. Everything that touches the natto in the early stages has to be cleaned with boiled water or you'll get rotten beans of the less desirable variety.

Within 20 hours, my soybeans had the distinctive smell and stringy consistency of genuine natto.

Yeah, just like the picture. I added warm water (previously boiled) mixed with sea salt, Japanese vinegar, sesame oil and a bit of soy sauce to taste. Note that the pot containing the beans should have some liquid on the bottom throughout the process so that the beans don't start to dry out and to facilitate the production of slime. Turning the beans and a small amount of liquid to keep things hydrated once or twice during the process seemed beneficial as well - I had been warned that natto should be cultured in a thin layer, and I nevertheless went ahead and made a whole kilo in a big pot, but it all turned out well.

I enjoy the taste of seasoned natto with thinly sliced green onions and plain rice. If you like a variety of cheeses and are not put off by a bit of slimy coating, chances are you'll also like natto. Bon appetit, or should I say, Tabete mimashou!