Japanese natto is a soybean product made by fermenting soybeans with natto bacteria, and it is a health food produced in Japan. Natto, which originated in ancient China, has been made since the Qin and Han dynasties (221 B.C.-220 A.D.), and was once called "edamame" in Japan, and the word "edamame" is also found in a wooden slip unearthed in Heijo-kyo. It is sticky, has a foul odor and a slightly sweet taste.

How to make natto

The traditional method of making natto is to wrap the steamed soybeans in straw, which is soaked in boiling water at 100 degrees Celsius to sterilize and keep it at 40 degrees Celsius for one day. The Bacillus subtilis (natto bacterium), which is commonly found on the straw, is heat-resistant due to the ability to produce bacillus spores, which does not destroy the sterilization process. produces a slimy, silky substance, a viscous appearance that comes mainly from the glutamic acid in the ingredients and is considered the source of Natto's delicious flavor.

In the late twentieth century, high-quality straw was harder to come by, and it was often sold in Styrofoam or paper containers. Therefore, the modern way of making natto is to use steamed soybeans mixed with artificially cultivated natto mushrooms and put them directly in a container to make them ferment, and some foods other than soybeans can also be made into natto.

In the case of sake, if the rice used to make the sake is contaminated with the natto bacteria, the rapid growth of the bacteria will inhibit the yeast needed to make the sake. Natto should not be present in the sake brewing premises, but other fermented foods may have a similar situation, so you need to pay more attention to the process.