1. Traditional Water Adding Method
Place the traditional Chinese medicine in a clay pot and spread it out with your hands. Then add water that is 3-4 centimeters higher than the level of the medicine (about the height of a pinky finger). This method is the simplest and most convenient, but it may be less accurate.
2. Weight-based Water Adding Method
In this method, the amount of water added is determined based on the total weight of the medicine. After preparing the Chinese medicine, weigh one patch (dose) of the medicine and calculate the total water amount based on the principle of adding 10 milliliters of water for every gram of medicine. Add 65% of the calculated water amount to the first decoction and reserve the remaining 35% for the second decoction. For example, for the nourishing tonic recipe of Ren Shen Yang Rong Tang, with a total weight of 150 grams, the water amount should be 1500 milliliters. 65% of this, which is 975 milliliters, should be added to the first decoction, and the remaining 35%, which is 525 milliliters, should be used for the second decoction. This method is more accurate, especially for complex Chinese herbal formulas with large amounts of medicine. Although this method may be more complicated than the previous two, it is more precise.
3. Measuring Device Water Adding Method
This method involves using a measuring cup or cylinder to add water, with different amounts of water added depending on the type of therapeutic medicine and the first and second decoctions. Shanghai Medicinal Herb Company has specified the following water amounts for different types of decoctions: for tonics and nourishing medicines, add 700-900 milliliters to the first decoction and 400-450 milliliters to the second decoction; for general medicines (mainly used to treat various diseases), add 500-700 milliliters to the first decoction and 300-350 milliliters to the second decoction; for medicines that relieve cold and flu symptoms, add 400-600 milliliters to the first decoction and 280-300 milliliters to the second decoction. This method is more accurate than the traditional water adding method, but if there is a larger quantity of medicine, the amount of water added may be relatively less.
In addition, if the medicine contains a large amount of flowers (such as Strobilanthes cusia flowers, Hedyotis diffusa flowers, etc.) or leaves (such as mulberry leaves, loquat leaves, etc.), it may be necessary to add slightly more water.
When hot water is poured into the raw medicine, the outer tissue of the medicine immediately coagulates and contracts due to the sudden impact of high temperature. In particular, proteins form an irreversible denatured layer on the cell wall, hindering the penetration of water. The effective components dissolved inside the tissue are also difficult to extract, greatly affecting the dissolution rate of the active ingredients. Therefore, it is important to avoid adding water when decocting the medicine.
