Onions have been widely eaten in China since ancient times as dishes, seasonings and health preservation. The Book of Rites records the uses of onions in many places, such as "fat onions", "shallots" and "it's good to cut onions". "Zhuangzi" said, "Spring drinks like onions to clear the five internal organs". "Guanzi" records that "the northern expedition is glorious, and winter onions are spread all over the world in Rong Lu", which is one of the records of the introduction of northern onions. In Hanshu, Gong Sui, the prefect of Bohai Sea, ordered people to grow onions. It also includes the problem of growing onions in the greenhouse. "Dongguan Han Ji" records that Kong Fen's wife "eats leeks". There are detailed methods of planting onions in Qi Yao Min Shu of the Northern Wei Dynasty, and onions are used as cooking condiments in many places. Louis, a Qing Dynasty man in the Five Dynasties, also pointed out: "Onions are delicious, but licorice is not as good as medicine. Therefore, China's old saying "Harmony is precious grass" ". Explain the seasoning function of onion in cooking. There are many poems about onions, such as Huang Tingjian's "Onion Mabel Miao, Sunflower Green", Chen Shidao's "Cooked Cake with Oil on Onion", Yelu Chuci's "Mix Peas and Onion" and so on.
Onions are mainly produced in Huaihe River, north of Qinling Mountains and the middle and lower reaches of the Yellow River Basin. According to the shape of pseudostems, they can be divided into long white type, and the pseudostems are tall and stout, such as Shandong Zhangqiu onion (up to 1m, weight 1.5kg), Shaanxi hua county onion, Liaoning Gaiping onion and Beijing Gaojiao onion. Medium white type, short pseudostems, swollen like chicken legs near the base. Famous products include Shandong Laiwu chicken leg onion, Hebei Longyao onion and so on. Short white type, closely arranged leaves, thicker and shorter than fake stems, and famous products include Shandong Shouguang Eight Leaf Paint.
Onions are widely used in cooking. Dishes can be used as ingredients, such as "yellow chicken with scallion", "fried duck heart with scallion", "fried sea cucumber with scallion" and fried bean curd with scallion. It can also be used as seasoning, such as steamed vegetables with shredded onion; Stir-fry with chopped green onion; Use onion juice to make shrimp paste; Boil with scallion; It can also be made into onion oil, which is essential for cooking.
Onion has a high nutritional value, containing 9 1g of water, 0.3g of protein 1g of fat, 5.2g of carbohydrate, 0.3g of dietary fiber/kloc-0, 60g of carotene, 0.03mg of riboflavin, 0.7mg of ascorbic acid/kloc-0, and 0.3mg of total vitamin E. The nutritional composition of shallots is slightly higher than that of scallions. In addition, onion also contains allicin, diallyl sulfur, linoleic acid, polysaccharide and so on. Its volatile components have antibacterial effect, and have certain curative effect on acute abdominal pain and dyspepsia in children caused by cold and ascaris. Traditional Chinese medicine believes that it is pungent and warm, and has the effects of relieving exterior syndrome, subduing yang and detoxifying. It can relieve exterior and interior, activate yang and promote blood circulation, dispel cold and stop bleeding according to fetus, and has a good therapeutic effect on colds and headaches. In recent years, medical research reports that the inhibition rate of scallion on cancer is over 90% after in vitro experimental screening.