What kind of apparatus is good for decoction? Pharmacists throughout the ages have attached great importance to this issue, there are many important discussions. Tao Hongjing of the Liang Dynasty said: "Warm soup do not use iron". Ming Dynasty Li Shizhen said: "decoction and avoid copper and iron ware, suitable for silverware tile pot." This is because copper and iron can be chemically altered with the active ingredients of many herbs.
Some after a long time of decoction to the liquid with rusty flavor, and even cause nausea and vomiting. Copper and tin Li pot can be decocted trace amounts of copper and tin ions. At present, the composition of some Chinese medicines is still unclear, with copper, iron utensils decoction will occur when the chemical reaction is still difficult to estimate, so should not be used.