1. Preparation of ingredients 

(1) Selection of ginger: To ensure quality, be sure to select certified  organic smaller-sized ginger.

(2) Fresh ginger slices: To clean the ginger roots, remove the soil, wash  thoroughly, and cut off the rotted portion. To make dried ginger  slices, cut the fresh ginger roots into 3 to 4 mm thickness (thinner  slices tend to break easily when drying in the sun or when frying). If  the fresh ginger slices are to be boiled to make ginger soup directly,  they can be cut into thinner slices.

(3) Dried ginger slices: Dry the fresh ginger slices in the sun (note:  if the slices cannot be dried in two days, they will likely become  moldy) or dry them in the oven, and then stir-fry for about 25  minutes on low heat to make dried ginger slices. Depending on the  place of origin and variety, 10 jin (catty/kati) of fresh ginger can be  made into 1.0 to 1.5 jin (catty/kati) of dried ginger slices.

(4) Ginger powder: Grind the dried ginger slices into fine powder. Sift  through a 100-120 mesh sieve to get the ginger powder

2. How to cook concentrated ginger soup

(1) Ginger dosage: For people with severe disease and illness, the  standard daily dosage of concentrated ginger soup is 500 to 750  grams of fresh ginger slices or 50 to 75 grams of dried ginger slices.

(2) Water quantity: Use 1 liter (1000 ml, approximately 5 bowls) of  water as the standard amount. If a larger amount of fresh ginger  slices is used, sometimes 1 liter of water is not enough to cover  the ginger slices; the amount of water must be increased until all  the ginger slices are submerged. (Whether it is with fresh or dried  ginger slices, use this standard amount of water for the first, second,  and third boil. However, for the second boil, the taste changes from  strong to weak, so with discretion, chili can be added to compensate  for the lessened effectiveness of the Heat Source.)

(3) Utensils and cooking methods: It is recommended that a ceramic  pot be used. With an ordinary stove or gas stove, start by cooking  with high heat, bring the soup to a boil, then turn to low heat, or boil with an electric Chinese herbal medicine pot. Cooking time  may range from 2 to 4.5 hours, depending on the appliance. While  cooking, try not to open the lid of the pot. 

(4) Concentration: The concentration of the soup is the key. The  amount of soup should be reduced to one-third of the original  amount of water used (e.g. If 5 bowls of water are used, boil until  1.7 bowls of water remains). If this amount is insucient for a oneday consumption, the amount of ginger slices and water should  be increased in the same proportion accordingly (e.g., 50 grams of  dried ginger / 5 bowls of water boiled down to 1.7 bowls of water  remaining, or 100 grams of dried ginger / 10 bowls of water boiled  down to 3.4 bowls of water remaining).

(5) Other: If you are worried about too much water retention in the  body, you can consume ginger pills, ginger powder, or ginger  powder paste instead.

Recommendations:

(1) After boiling the ginger soup, filter with a strainer. The hot ginger  soup should be stored in a thermos and consumed as needed.  However, it should not be stored for more than 12 hours. If you  sense the taste has changed, it means the ginger soup is spoiled and  should not be consumed!

(2) Keep all fresh ginger that will not be used immediately in the  refrigerator. Dried ginger slices and ginger powder must be stored  in a tightly sealed container, and for long-term preservation, the  ginger must be refrigerated.