How to reveal the ancient people in China, fermented vinegar?

The earliest recorded method of making vinegar is probably the Book of Food written by Xie Yan, a native of Han Dynasty, which mentioned "the method of making Millennium bitter soybean wine", but it is too simple to estimate the level of that method. The earliest book that records the method of making vinegar is Qi Yaomin's Book, in which there are not only many methods of "bitter wine", but also many methods of making koji and vinegar. For example, there are 23 * * methods, such as "magic method of glutinous rice (sticky sorghum)", "koji method of millet (millet with skin)", "wine returning" and "magic method". Raw materials for vinegar production include millet, sorghum, glutinous rice, barley, wheat, soybeans and adzuki beans. He introduced the method of making fine balsamic vinegar. Take "magic" as an example, the method is as follows: first, make vinegar koji, cook soybeans and mix them with flour, add water to make cakes, spread them flat, cover them with leaves, and let bacteria multiply on the cakes. Aspergillus spores germinate a few days later, giving birth to hyphae, and then the hyphae give birth to a large number of yellow-green spores all over the koji. This kind of yellow song was called "yellow steaming" in ancient times. On the seventh day of the seventh lunar month, the bran steamed with three hooves (Hu, one hoof is ten buckets) is added with "yellow steaming" and placed in a clean pottery jar. When these two things get hot when they are in contact, they are mixed together and added with water until they are just submerged. Keep the temperature for two days, squeeze out the clear liquid and put it into the big urn. After two or three days, the urn will be hot, and the outer wall of the urn should be cooled by pouring cold water. At this time, white foam will appear on the liquid surface (called "white fermented grains"), which should be picked up and skimmed in time (otherwise, the fermentation broth will not get enough oxygen, which will hinder the growth of acetic acid bacteria, while anaerobic butyric acid bacteria will take the opportunity to develop and vinegar will not be made). A month later, "God Vinegar" is ripe and ready to eat. It can be seen from the description of various vinegar making methods in Qi Yaomin's Book that during the Northern Wei Dynasty, China vinegar makers made detailed observations on several key links in the process of vinegar making, and their series of judgments also conformed to the truth of modern science, indicating that the achievements of vinegar making technology have reached a high level. Although Qi Yaomin's Book does not explicitly mention "aged vinegar", it has been mentioned in the barley retting method that clear vinegar (fresh vinegar with odor removed) "has to be put into the pot and stopped for several years", that is, sealed storage and aging for several years, which is obviously more mellow aged vinegar.

In the Eastern Han Dynasty, vinegar was not only edible, but also began to be used as medicine. According to legend, Zhang Zhongjing, a famous doctor in the Eastern Han Dynasty, used "Huangqi Shaoyao Guizhi Kujiu Decoction" to treat yellow sweat (the name of the disease is edema of the head, face and limbs, yellow clothes sticking like cypress juice, backache and unfavorable urination). Tao Hongjing's "A Record of Famous Doctors" said that vinegar can "eliminate carbuncle, reduce swelling, dissipate moisture, and kill evil spirits". After the rise of alchemy, bitter wine was quickly used by alchemists. It is said that they made a solution with bitter wine and saltpeter, which actually dissolved many minerals (turned into water), such as cinnabar, thorn stone, realgar and so on. (This is greatly exaggerated, of course), so it became the main solvent of "water alchemy". The alchemist also dissolved some minerals in vinegar, which is called "Zuo Wei Huachi" and is also an indispensable medicine in alchemy.

At the latest in the Sui and Tang Dynasties, China not only mastered the continuous process of making vinegar with grain as raw material through direct koji-making and fermentation, but also made vinegar with more diverse raw materials, indicating that extensive attempts were made, so the varieties of vinegar were extremely rich. According to Su Jing's newly revised Materia Medica, there were not only grain vinegar such as rice vinegar, wheat vinegar, bran vinegar, koji vinegar and distiller's grains vinegar, but also sweet and sour vinegar with caramel as raw material and fruit vinegar with peach, grape and jujube as raw materials. Of course, the most important thing is rice vinegar, its taste is the most "sour", and only it can be used as medicine.