How to make natto

The ancient Japanese book, Wakan Sansai Toukai, states, 'Natto has been made since the Qin and Han dynasties.' The word "tempeh" is also used in Japan for natto, which started in China, and is also found in a wooden slip unearthed in Heijo-kyo. Since edamame was made and stored in urns at the nasho of a monastic temple, and then spread to Japanese temples by Zen monks from the Qin and Han dynasties, natto was first developed in temples, and was also called "tang natto" or "salted natto". Subsequently, natto was developed according to the local environment, such as using soy sauce instead of edamame or soy sauce instead of soy sauce in Japan. In Japan, local specialties have been passed down based on the characteristics of each region, such as the natto of Oryuji, Daitokuji, Ichigo, Hamana of Daifukuji, and Yabashi of Goshinji.

How it is made Editor

Traditional Mito Natto wrapped in straw

Traditional Mito Natto wrapped in straw

The traditional method is to wrap steamed soybeans in straw, which is then soaked in boiling water at 100 degrees Celsius to sterilize them and kept at 40 degrees Celsius for a day. Spores and high heat resistance, the sterilization process is not damaged, high temperature culture speed can also inhibit other strains of bacteria, and make soybean fermentation produces sticky filaments, this sticky appearance mainly from the ingredients in the glutamic acid, is considered to be the source of natto delicious.

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 ferment them, and some foods other than soybeans can also be made into natto.

Modern factory-made natto

Modern factory-made natto

In the case of sake brewing, if the rice used as raw material is inadvertently contaminated with the natto bacteria, the yeasts required for brewing are inhibited by their rapid reproduction. Natto must not be present in the sake brewing premises, but other fermented foods may be similarly affected, so the process requires careful attention.

Natto bacteria are weakly acidic, and can hinder the production of lactic acid by lactobacilli. Technically, we have developed natto with a weaker odor, but the use of natto strains with lower viability can easily create room for other bacteria to proliferate. In addition, the natural enemy of the natto bacteria is the phage virus that parasitizes the bacteria. When the phage begins to act, it reduces the activity of the natto bacteria and may cause other bacteria to begin to multiply, so you should avoid consuming natto that has exceeded its shelf life.

How to eat

Traditionally, natto is mixed with soy sauce or wasabi (the boxed natto sold in department stores is usually made with light soy sauce and yellow wasabi) until a silky texture appears, and then eaten on top of white rice, which is called natto rice. Some people also mix natto with various ingredients such as raw eggs, green onions, minestrone, daikon radish, and shiba fish. In Hokkaido and Tohoku, natto is sometimes mixed with sugar. There is also a creative way to eat natto with mayonnaise. If you add the sauce without mixing it, it will become too watery and lose its consistency, while green onions and wasabi suppress the pungent odor of "natto ammonia". Those who are not used to eating natto think it is rotten boiled soybeans.

Nutrition Editor

Natto contains all the nutrients of soybeans and special nutrients added by fermentation, including saponins, isoflavones, unsaturated fatty acids, lecithin, folic acid, edible fibers, calcium, iron, potassium, vitamins, and a variety of amino acids and minerals, which make it suitable for long term consumption and health maintenance.

Japanese medical doctors and physiologists have learned that the protein of soybeans is insoluble, and after making natto, it becomes soluble and produces amino acids, and various enzymes that do not exist in the raw materials are produced due to the natto bacteria and associated bacteria, which help the stomach and intestines to digest and absorb. The composition of natto is: 61.8% water, 19.26% crude protein, 8.17% crude fat, 6.09% carbohydrates, 2.2% crude fiber, 1.86% ash, and as a plant food, it is the richest in crude protein and fat. Natto Department of high-protein nourishing food, natto contains enzymes, consumption can be excluded from the body part of the cholesterol, decomposition of the body's acidified lipids, so that abnormal blood pressure back to normal.