The earliest record of natto in Japan dates back to about 900 years ago (1053 A.D.), when the word "natto" appeared for the first time in a book called "Shin-Saru Raku Ki," written by a Japanese man named Fujiwara Akihira. According to this book, Natto is Nasho no Dou. The word "naso" means temple kitchen. Natto was also called "temple natto" because it was a fermented food that was widely eaten by monks in ancient Japanese temples. At that time, natto was made by fermenting steamed soybeans by exposing them to airborne natto bacteria, soaking them in salt water, and then drying and preserving them for consumption. Natto made from beans was the main source of protein intake for monks at that time. Later on, the method of making natto evolved, and the Japanese wrapped soybeans in straw after they were cooked and used the natto fungus on the straw to fully ferment the soybeans. The natto made in this way has a distinctive flavor, a sticky appearance, and long, thin strands of natto when picked up by chopsticks, just as we see today. The modern natto production has been the use of biological high-tech methods, under the control of hygienic conditions without bacteria, will be steamed soybeans with excellent purebred natto bacteria fermentation, quality and stability and efficacy of the biotechnology products.

One, the use of vessels and materials ① soybean 500g ② natto bacteria 0.3g or natto half a box (25g) ③ pressure cooker ④ stainless steel pot ⑤ foam lunch box and other shallow containers ⑥ foam box ⑦ 2 liters of rectangular plastic bottles or warm water bag ⑧ thermometer, steam soybean soybean fully washed, add 3 times the amount of water soaked overnight, pour off the water and put it into a pressure cooker steam to the extent that soybeans with the degree of crushed hands, about 45 minutes. About 45 minutes. If you don't have a pressure cooker, it's okay, but don't put too much water in the cooker at once. In order to maintain the original flavor of the soybeans, it is best to steam them. Third, inoculation of natto bacteria natto bacteria in the appropriate temperature, 30 minutes will be able to proliferate about two times. So 500g of dry soybeans, the amount of natto bacteria need only 0.3g. Dissolve it in 50ml of hot water, add it evenly to the hot soybeans, quickly stirred well, divided into 7 foam lunch box, thickness of about 2cm, the top thatched with gauze or in the lunch box and the lid of the lunch box with a pair of chopsticks between the frame, so that it is fully exposed to air. Since natto is an oxygen-loving bacteria, it is important for it to be exposed to air. However, after fermentation, close the lid and seal the mouth with tape. If you use natto, choose your favorite kind of soybeans, freeze them, and use them as strains. 500g of dried soybeans can be used for half a box of natto bacteria (50g per box). Add it to the hot soybeans in the same way as above. Ferment for 14-15 hours at a constant temperature. Put a few rectangular plastic bottles filled with 50℃ hot water in a large clean foam box and place the foam lunch box inoculated with natto bacteria on top of the bottles. The ideal temperature inside the box is 42℃. If the temperature inside the box drops to 37℃, replace the bottles with 50℃ hot water. Repeat this process of replacing the hot water in the bottle for 14-15 hours, and the soybeans will become natto when a white film is formed on the surface of the soybeans and sticky threads appear. Cover tightly and store in the refrigerator at low temperature. If you don't have a foam box, you can use a large cardboard box surrounded by a quilt and an electric mattress, or insert a 45℃ light bulb into the box to keep it at a constant temperature. Pay attention to more contact with the air. After fermentation at a constant temperature of 40℃-42℃ for 14-15 hours, and then put it in the refrigerator for a few hours to cook at a low temperature, the natto will have a better appearance and taste. Therefore, it is recommended to cook the natto in the refrigerator for several hours before consumption. The preservation of powdered natto mushrooms is particularly stable in the spore state, so it can be preserved for a long time as long as it is kept in a cool and dry place. However, after opening, it must be stored in the refrigerator at low temperature. Seven, the production of the key ① pay attention to maintain a constant temperature of 40 ℃ -42 ℃. ② Natto bacteria should be inoculated into the hot soybeans. Eight, precautions cardiovascular disease patients taking blood coagulation blocking agent new coumarin, vk2 can make the new coumarin to lose efficacy, so do not eat natto. Scientific methods of consumption of natto although it has a high medicinal value, but because of its unique odor and sticky silk, so that part of the people on it to stay away. How to eat natto so that the odor disappears and the stickiness decreases? For those who hate the smell of natto, you can neutralize the smell of natto with some fragrant foods such as green onions, scallions, shrimp, and small fish, etc., and at the same time improve the ability to resist acidification. For those who hate the stickiness of natto, you can dilute natto 1-2 times with water and eat it with soy sauce and other seasonings. You can also chop up natto and add it to cold soup. The best scientific combination of natto: 1. natto + green onion 2. natto + white radish 3. natto + Korean cabbage 4. natto + raw egg yolk 5. natto + kelp 6. natto + sesame + honey how to improve the health effects of natto 1. natto for dinner is the best. Through experiments, Prof. Yoshiyuki Sumi believes that: between 1 hour and 12 hours after consuming Natto, Natto activating enzyme plays the function of dissolving blood clots. According to statistics, cerebral infarction, myocardial infarction and other thrombosis diseases, the onset of most of the time in the early morning and Monday. Therefore, it is best to eat it every night or at dinner on Sunday. 2. Eat it without heating as much as possible. Natto activating enzyme is not heat-resistant, heating to 70 ℃ activity will disappear. Therefore, it is best to take it raw. 3. Eat it every day. After Nattokinase enters the body, its activity is maintained for about half a day. Therefore, it is ideal to eat 30g or 100g of it every day.4. You can eat it even after the shelf life. The shelf life of natto is one week, it is stored in the refrigerator at low temperatures, but also in the slow low-temperature ripening and fermentation, natto enzyme and vk2 is also increasing. However, even though you can eat it after the expiration date, the natto bacteria continue to break down proteins in order to survive, and as a result, the odor gradually increases. Where to buy natto Natto (natto) is the scientific name for the fungus Kochia. It is produced by accidental contact between cooked soybeans and straw. In Japan, natto is traditionally made by putting cooked soybeans in a container made of straw while they are still hot and fermenting them naturally with the natto bacteria attached to the straw. Natto made in this way contains not only natto bacteria, but also other stray bacteria, which is not only unsanitary, but also of poor quality.