TCM Medicinal Soup: Stewed Old Duck for Autumn Dryness Relief

Introduction to Medicinal Diet

Radix Adenophorae (adenophora root) and Radix Asparagi (asparagus root) braised with old duck is a classic TCM medicinal diet, derived from the variation of the folk “clear-supplement-cool” soup from the Lingnan region. The main ingredients are Radix Adenophorae and Radix Asparagi, both of which are yin-nourishing herbs, paired with old duck, and seasoned with Rhizoma Zingiberis Recens (fresh ginger) and cooking wine. This medicinal dish blends the sweet-moistening properties of the herbs with the rich savor of poultry, resulting in a clear broth with a sweet, fresh taste. It is especially suitable for consumption during the dry autumn season or by those who spend prolonged periods in air-conditioned environments. The original intention behind its creation was to utilize the principle of “homology of medicine and food” to help the body ward off the pathogenic factor of “warm-dryness,” compensating for the deficiency of yin fluid caused by excessive sweating or fluid depletion. For this reason, it is often hailed by TCM health preservationists as “the first soup of autumn.”

In the traditional medicinal diet system, Adenophora root (Adenophorae Radix) and Asparagus root (Asparagi Radix) are both classified as herbs that nourish yin and moisten the Lung, while old duck (mature duck) is cool in nature and can nourish yin and tonify deficiency. When combined, these three ingredients enhance the clearing-moistening effect without being overly cloying. This medicinal diet is not only a delicious soup but also a vivid embodiment of the TCM concept of “treating disease before it occurs”—using dietary regulation to restore the balance of yin and yang during seasonal transitions or at the first signs of dryness in the body. It is simple to prepare, mild in taste, and suitable for all ages; however, it is essential to differentiate body constitution to avoid inappropriate use.

Efficacy of Medicinal Diet

The core efficacy of “Stewed Old Duck with Glehnia Root (沙参) and Asparagus Root (天冬)” lies in “nourishing yin and moistening the lungs, clearing heat and generating fluids.” Glehnia root (沙参) can nourish yin, clear lung heat, and benefit the stomach to generate fluids. It is effective in alleviating dry cough due to lung heat and chronic cough due to deficiency strain. Asparagus root (天冬) excels in nourishing kidney yin, descending deficient fire, and also has the effect of moistening the intestines to promote bowel movements. The combination of the two enhances the nourishing action on the Lung, Stomach, and Kidney meridians. As a substance of blood and flesh, old duck can supplement the middle and boost qi, nourish yin and supplement blood. Furthermore, its nature is relatively cool, enabling it to clear deficient heat. When paired with these medicinal herbs, it can significantly improve symptoms such as dry mouth and tongue, sore throat, and dry cough with scant sputum caused by yin deficiency with internal heat.

From a modern nutritional perspective, old duck is rich in high-quality protein, B vitamins, and various minerals, with moderate fat content that is primarily unsaturated fatty acids, which helps enhance immunity. Glehnia root (Sha Shen) and Asparagus root (Tian Dong) contain abundant active compounds such as polysaccharides and saponins, exerting good anti-inflammatory, antioxidant, and immunomodulatory effects. Therefore, this medicinal dietary recipe is not only suitable as a health-maintaining soup in dry climates, but also beneficial as an adjunctive recuperative support for patients in the recovery phase of chronic bronchitis and pulmonary tuberculosis, helping to relieve dry cough, night sweats, and other discomforts.

Actions of Traditional Chinese Medicine

Glehnia root (Sha Shen, *Glehnia littoralis* or *Adenophora stricta*) is sweet and slightly bitter in taste, slightly cold in nature, and enters the Lung (LU) and Stomach (ST) meridians. Its main actions are to nourish yin, clear the lung, benefit the stomach, and engender fluids. The *Compendium of Materia Medica* records that it “clears lung fire and treats chronic cough with lung flaccidity.” Asparagus root (Tian Dong, *Asparagus cochinchinensis*) is sweet and bitter in taste, cold in nature, and enters the Lung (LU) and Kidney (KI) meridians. It excels at enriching the kidney and moistening the lung, clearing heat and nourishing yin, and is often used to treat yin deficiency dry cough and consumptive cough with hemoptysis. Old duck is sweet and salty in taste, cool in nature, and enters the Spleen (SP), Stomach (ST), Lung (LU), and Kidney (KI) meridians. It greatly tonifies deficiency and fatigue, nourishes yin and nourishes the stomach, and promotes urination to reduce edema. When combined, Glehnia root focuses on clearing heat from the lung and stomach, Asparagus root addresses both lung and kidney yin deficiency, and old duck provides a rich foundation of yin fluid nourishment. Together, they form a comprehensive effect of “clearing lung fire above, nourishing stomach yin in the middle, and enriching kidney water below.”

Based on Traditional Chinese Medicine theory, the human body is prone to developing the pattern of “Lung Dryness with Fluid Deficiency” (肺燥津亏) during autumn or under consumptive states, characterized by dry mouth and nose, dry cough without sputum or with scanty, sticky sputum, and dry stools. The medicinal food of Adenophora/Glehnia root (沙参) and Asparagus cochinchinensis (天冬) stewed with old duck combines the method of “sour-sweet transforming yin” (酸甘化阴) with “blood and flesh replenishing essence” (血肉填精). This approach not only directly supplements body fluids but also reduces the consumption of yin fluids by regulating the functions of the zang-fu organs. It is particularly noteworthy that although Asparagus cochinchinensis (天冬) is cold in nature, the warm and moistening quality of the old duck can moderate its coldness. The addition of fresh ginger (生姜) helps prevent the formula from becoming overly cloying, ensuring that the entire medicinal food is balanced and suitable for long-term nourishment.

Indications

This medicinal food is most suitable for individuals with a constitution of Yin deficiency with Lung dryness, commonly presenting with symptoms such as dry cough with scanty sputum, blood-tinged sputum, dry and itchy throat, hoarse voice, and dry nose with epistaxis. It is especially beneficial during autumn and winter or for those who work long hours in dry environments (e.g., air-conditioned or heated rooms), such as office workers, teachers, and singers who overuse their voices, as it effectively moistens the throat and alleviates discomfort. For those suffering from Yin deficiency dry cough due to conditions like chronic bronchitis, convalescence from pneumonia, or pulmonary tuberculosis, it can serve as an adjunctive dietary therapy to help repair damaged mucosal tissues.

Additionally, it is suitable for those with Yin Deficiency and Fire Hyperactivity (manifested as heat in palms and soles, malar flush, night sweats, dry mouth with desire for cold drinks, red tongue with scant coating). For women experiencing perimenopausal hot flashes, irritability, and insomnia due to Kidney Yin insufficiency, this soup can nourish Yin and reduce Fire. Moreover, individuals with Fluid depletion from chronic熬夜 (e.g., dry eyes, dry mouth, rough skin) are also recommended to consume it regularly to harmonize Yin and Yang and restore vitality.

Contraindicated populations

Individuals with Spleen-Stomach Deficiency-Cold Pattern should use caution. Both Adenophora root (Sha Shen) and Asparagus root (Tian Dong) are cold in nature, and although old duck can nourish Yin, it is also relatively cool. For individuals with a Yang deficiency constitution who typically experience aversion to cold, cold pain in the epigastric region, loose stools, or poor appetite with abdominal distension, consumption may increase the burden on the Spleen and Stomach’s transformation and transportation functions, potentially leading to diarrhea or indigestion. It is recommended that such individuals either consume these foods in small amounts after combining with warming-the-Middle-Jiao herbs such as Ginger (Sheng Jiang) and Aged Tangerine Peel (Chen Pi) under the guidance of a physician, or avoid them altogether.

People with patterns of abundant dampness with profuse phlegm, as well as those with wind-cold common cold and cough, also fall under the category of contraindications. If there is a white, greasy tongue coating, cough with profuse clear, thin phlegm, or accompanied by a wind-cold exterior pattern such as nasal congestion with clear watery discharge, consuming this medicinal diet will “close the door and trap the bandit” (i.e., retain the pathogenic factor), making it difficult to expel the dampness or cold pathogen, and instead aggravating the condition. Additionally, for diabetes patients, since the old duck soup may contain many seasonings and Asparagus cochinchinensis (Tian Dong) contains certain sugars, it should be consumed cautiously under blood glucose monitoring, and it is recommended not to add rock sugar or honey.

Ingredient Formula Ratios

Main ingredient: Half an old duck (approximately 600–800 g, preferably white duck or mallard duck raised for over one year). Medicinal herbs: 15 g *Bei Shashen* (Glehnia root, *Glehnia littoralis*), 10 g *Tian Dong* (Asparagus root, *Asparagus cochinchinensis*; if using fresh Asparagus root, increase to 20 g). Auxiliary ingredients: 3–5 slices of aged ginger (approximately 10 g), 10 ml cooking wine, 3–4 g salt (for final seasoning), and optionally 5 g *Gou Qi Zi* (Goji berry, *Lycium barbarum*) and 2–3 red jujubes (*Ziziphus jujuba*) to add sweetness.

The following is a reference dosage for one person (can be divided into two servings). For a family of 3–4 people, increase the old duck to one whole duck (approx. 1200–1500 g), double the herbs: 30 g Glehniae Radix (Coastal Glehnia Root) and 20 g Asparagi Radix (Asparagus Root), and increase the supplementary ingredients proportionally. Note that the dosage of Asparagi Radix should not be excessive, as its cold nature may cause diarrhea if used in excess. When purchasing herbs, choose intact, dry products without mold or spoilage. Glehniae Radix is best when the roots are thick, white, and firm; Asparagi Radix is optimal when it is plump, yellowish-white, and semi-transparent.

Cooking Method

Step 1: Pre-treatment of medicinal herbs. Rinse Glehnia littoralis (Coastal Glehnia root) and Asparagus cochinchinensis (Asparagus root) with clean water, place them in a bowl, and soak in warm water for 30 minutes until softened. Drain and set aside (do not discard the soaking water—it can be reserved for later use). Slaughter the old duck, remove the feathers and internal organs, and chop into medium-sized pieces (approximately 4–5 cm square). Soak the pieces in cold water for 20 minutes to remove blood, then drain well.

Step 2: Blanch to remove fishy smell. Add enough cold water to a pot, place the duck pieces in, then add 2 slices of ginger and 5 ml of cooking wine. Bring to a boil over high heat and continue boiling for 2–3 minutes, skimming off any foam. Remove the duck pieces and rinse them thoroughly with warm water. Note: Do not rinse with cold water, as this may cause the meat to contract and become tough. After blanching, the broth will appear clearer and the fishy smell will be significantly reduced.

Step 3: Stewing. Place the blanched duck pieces, the soaked [Radix Adenophorae (Adenophora Root)] and [Radix Asparagi (Asparagus Root)] (along with the soaking water) into a stewing pot or clay pot. Add enough hot water (to cover the ingredients by about 3 cm) and the remaining ginger slices and cooking wine. If using a stewing pot, cover the lid and steam over water for 2 hours. If using a clay pot, bring to a boil over high heat, then reduce to low heat and simmer for 1.5–2 hours, until the duck meat can be easily pierced with chopsticks. Add the [Fructus Lycii (Goji Berry)] and [Fructus Jujubae (Chinese Date)] during the last 5 minutes. Before turning off the heat, season with salt and stir well.

Usage Tips

1. Optimal consumption timing: This soup should be taken warm, about 1 hour after lunch or before dinner, in small bowls of approximately 200–250 ml each. Avoid drinking large amounts on an empty stomach. After 2–3 consecutive days of consumption, take a 1-day break to observe the body’s response. It is recommended to take 2–3 times per week; after improvement of Yin deficiency symptoms, the frequency can be reduced to once per week.

2. Seasoning and Pairing: As the medicinal diet is cooling in nature, a sprinkle of chopped scallions or fresh cilantro (coriander leaf) may be added when consuming to awaken the Spleen and stimulate the appetite. If the soup tastes mild, a few drops of sesame oil or a pinch of white pepper can be included, but spicy-hot condiments such as chili peppers and Sichuan pepper should be avoided, as they may counteract the Yin-nourishing effect. During the course of consumption, avoid spicy, fried, and grilled or barbecued foods.

3. Special Population Precautions: Pregnant and lactating women should consult a TCM practitioner before consumption, as Asparagus cochinchinensis (Tian Dong, Chinese Asparagus root) is Cold in property and its effects on the fetus are not yet clearly understood. For children (aged 3 and above), a small amount may be consumed, but the herb should be removed, and only the soup and meat taken, with the dosage reduced by half. Discontinue use during unresolved common cold or fever, and resume only after full recovery. If the soup is not finished in one sitting, it should be stored in a refrigerator and consumed within 24 hours after reheating. Do not refreeze.