Measure about two cups of dried soybeans, about 200g, with the measuring cup used to make rice in the rice cooker. (For 1L yogurt maker is 110g soybeans, if 1.5L\yogurt maker, 200g dry soybeans) Soak soybeans in water for about 12 hours.

Step 2: Steaming

Put the soaked soybeans into the pressure cooker, add 5% sugar and 1% monosodium glutamate (MSG), pour in the right amount of water, steam over high heat for 5 minutes, turn on the heat and cook for 35-40 minutes, turn off the heat. Remember that you must steam the beans, the beans are cooked to the extent that the hand gently pinched deflated, but the beans are still whole.

Step 3: Inoculation

Open a capsule of Natto Mushroom and dissolve half of the capsule (Natto Lead) in 30 ml of water. Let the beans cool down to about 35°, take two milliliters of the natto bacteria solution and pour it into the beans, stirring evenly. Stir as much as you can, then pour it into the basket where you made the natto, cover with wet gauze, put it into the yogurt maker, and cover with the outer lid (leave the lid of the inner container uncovered). If the temperature is low in the northern winter, you can put a moderate amount of warm water between the inner and outer liner of the yogurt maker in order to increase the temperature.

Step 4: Fermentation

Plug in the yogurt machine power supply, start fermentation, fermentation time 16-24h, decided by the individual, the end of the fermentation is based on the natto with chopsticks to stir a little, can pull out a lot of silk.

Step 5: Storage and Cooking

After making the natto, if you can't finish it at one time, you can put it in the refrigerator for freezing and preserving, usually not more than 10 days. When you consume it again, when you take the natto from the refrigerator to room temperature, the natto will undergo a second fermentation, which will increase the degree of fermentation of the natto, and this process is also called after-ripening. Note that all containers and utensils that come into contact with the beans must be sterilized with boiling water beforehand!