A bowl of decoction made from medicinal herbs is brownish-black in color, turbid in appearance, and bitter in taste. When taken warm, there is often a muddy sediment at the bottom of the bowl. Because herbal medicines themselves have certain colors, people often assume that the decoction will be brownish-black in color after boiling, and rarely give it much thought. As for the bitter taste, people often have a saying as a basis for understanding, which is "Good medicine tastes bitter and is beneficial for the illness." Therefore, the bitterness of the medicine is not seen as a bad thing, but rather a perspective of finding pleasure in bitterness. The turbidity of the decoction is a common concern, with many people unsure whether it is good or bad. As for the muddy sediment at the bottom of the bowl, whether to mix it with water or discard it is a practical issue that should not be underestimated, as it directly affects the efficacy of the medicine.
In order to determine whether the muddy sediment at the bottom of the bowl of decoction made from co-boiling Coptis and Licorice should be consumed or discarded, let us now give a general introduction to the possible outcomes when co-boiling these two herbs. Modern scientific research has shown that the main active ingredients in Coptis are berberine and other alkaloids, while the main active ingredients in Licorice are glycyrrhizic acid and glycyrrhetinic acid. These two types of ingredients have high solubility in water, so they can dissolve from the herbal pieces into the water during boiling. When the two herbs are co-boiled, the berberine from Coptis and the glycyrrhizic acid from Licorice can meet in the water, forming salts or complexes with lower solubility in the liquid. This results in fine solid particles suspended in the decoction, causing it to become turbid. If this decoction is left undisturbed, it may precipitate at the bottom of the bowl, forming a muddy sediment. Some people have conducted experiments co-boiling Coptis and Licorice with water. If a large amount of Licorice is used, the resulting decoction, when left to settle, can produce a clear liquid which is not bitter, but the antibacterial effect is greatly reduced. This indicates that berberine, which has a bitter taste and antibacterial effect, is deposited at the bottom of the bowl, within the muddy sediment. Therefore, if a prescription containing both Coptis and Licorice is co-boiled, and the resulting decoction is left to settle in the bowl, it is obvious that discarding the muddy sediment will affect the efficacy. The correct approach is to add some water to the muddy sediment and stir it, then consume the mixture. This is appropriate. Traditional Chinese medicine has many famous formulas that contain both Licorice and Coptis, such as Huanglian Tang in "Treatise on Febrile Diseases" (composed of Coptis, dried ginger, cinnamon twig, pinellia tuber, codonopsis root, Licorice, and jujube), and Ge Gen Huang Qin Huang Lian Tang (composed of kudzu root, Scutellaria baicalensis, Coptis, and Licorice), as well as Shao Yao Tang in "Preserve Life Collection" (composed of peony root, Scutellaria baicalensis, Chinese angelica, areca husk, Coptis, rhubarb, Aglaia odorata, Licorice, and cinnamon). When the decoction is made, if there is a muddy sediment at the bottom of the bowl, it is advisable to mix it with water and consume it, or simply stir the entire bowl of decoction before consumption. Other decoctions made by co-boiling these two herbs should be consumed in the same manner.
Berberine belongs to alkaloids, which are alkaline compounds. There are many Chinese herbs that contain alkaloids, such as Aconitum, Aconitum carmichaelii, Ephedra, Radix Stephaniae Tetrandrae, Fritillaria, and Sophora flavescens. Glycyrrhizic acid belongs to acidic substances, and there are also many Chinese herbs that contain acidic components, such as rhubarb and Prunus mume. When a prescription contains Chinese herbs with alkaloids and herbs with organic acids, the resulting decoction from co-boiling these herbs should also be consumed by stirring the muddy sediment. On the other hand, alkaloids can not only form insoluble salts with organic acids, especially large molecular organic acids, but also form insoluble complexes with tannin glycosides. There are many Chinese herbs that contain tannin glycosides as well. Although it has not been fully clarified which substances insoluble in water are formed between these herbs, and whether they are effective or not, for safety reasons and to ensure efficacy, it is still advisable not to discard the muddy sediment, but rather consume it if possible.
Although ancient medical practitioners did not know which compounds could produce insoluble substances in water, or in other words, they did not understand the principle of the formation of sediment in co-boiling, they had already noticed in clinical practice that the sediment should not be easily removed. One of the methods used was filtering the medicinal liquid, allowing the sediment to enter the liquid for consumption. Even today, this method is still used, with only a layer of coarse gauze or mesh used for filtration. In summary, when drinking Chinese herbal decoctions, although they may be turbid, there is a reason behind it, so do not strive for a clear and easy-to-drink liquid. It is best to consume the entire decoction.
