Pick out the impurities from the raw materials, remove the remaining roots and those materials with larger hollow, divide them into different grades according to its size and wash them.
Soak the clean astragalus membranaceus in water for 2-4 hours, then take it out and put it in the moisturizing medicine box. Operating the aforementioned process for 12-24 hours, spray water 1-2 times every 3 hours. The amount of water spraying on the tail should be less, and more water should be sprayed on those with thicker strips. You should frequently turned over the medical materials until the humidity inside and outside is same, and the cut surface is free of dryness. When it is qualified by the bending method, it is ready for cutting.
Using a rotary slicer to cut it into oblique slice or thick slices. The thickness of the slice is about 2-4 mm.