China's yam producing areas are mainly Henan, Jiangsu, Guangxi, Hunan and other places.
However, Huaiqing, Henan Province has the best quality and is regarded as an authentic medicinal material.
Digging out after the first frost, scraping off the rough skin, drying in the sun or drying in the sun, called hairy yam; Then soak it soft and stuffy, rub it into a cylinder, dry it and polish it, which is called Guangyam.
Planting history of Chinese yam
Yam has a long history of cultivation in China.
The name has been changed several times.
Shan Hai Jing called it Hugh.
China's earliest pharmaceutical monograph "Shen Nong Ben Cao Jing" called it yam, also known as sweet potato.
Upp materia medica called it Yu Yan.
It is said that yam was renamed to avoid the taboo of the Tang and Song emperors. Song Kou Zongshuang's Materia Medica changed the real name of Dioscorea opposita to Dioscorea opposita in order to avoid the taboo of (Shu) and (Yu).
Edible value of yam
Yam is an ancient vegetable, which is also regarded as a good tonic and is deeply loved by the world.
Lu You, a great poet in the Southern Song Dynasty, praised the cloud in Taking Yam Sweet Soup: I used to live in a handful of grass by the lake, but I used to drink yam in the village.
Since then, Babel has avoided giving up, and the taste of Tiansutuo is sweet.
As a daily vegetable, Chinese yam is loved not only by China people, but also by Japanese people.
In addition to boiled yam, the Japanese also like yam mud made of raw yam.
Put the ground yam mud into soy sauce and other seasonings, stir well and cover with rice. This kind of rice is called yam mud with rice.
Medicinal value of yam
Yam was first used as medicine in Shennong Materia Medica Classic, which means that it can treat main injuries, tonify deficiency, dispel pathogenic factors of cold and heat, tonify middle energizer, promote granulation, and be smart for a long time.
Be listed as top grade.
There is yam in Materia Medica, which belongs to food. The ancients used decoction, saying that it can strengthen the spleen and replenish qi, and clear away heat and fire.
The temperature is mild, which supplements the yin of spleen and lung, so it can moisten fur and increase muscles.
Its astringency can cure nocturnal emission.
It is sweet and salty, and it is beneficial to kidney and yin. Although yin is not very stagnant, it can seep dampness and stop diarrhea. Compendium of Materia Medica says that it can benefit kidney-qi, strengthen spleen and stomach, stop diarrhea, eliminate phlegm and promote fluid production, and moisten fur.