Mao Gen Pig Lung Soup: Traditional Chinese Soup for Lung Health

Introduction to Medicinal Diet

Mao Gen Pig Lung Soup is a classic heat-clearing and lung-moistening medicinal diet originating from the Lingnan region. It is made by slow-cooking fresh Imperatae Rhizoma (Mao Gen, cogongrass rhizome) and pig lung as the main ingredients, supplemented with honey dates, Citri Reticulatae Pericarpium (Chen Pi, tangerine peel) and other seasonings. Imperatae Rhizoma is the rhizome of *Imperata cylindrica* (Poaceae) and has long been used in Traditional Chinese Medicine as a diuretic and heat-clearing herb. Pig lung is considered a prime example of “like supplements like” (Yi Xing Bu Xing), especially suitable for individuals with lung deficiency and cough.

This soup has a clear broth, a sweet taste, and a delicate fragrance. It serves both as a nourishing daily family soup and as a restorative remedy for seasons of spring dampness and autumn dryness that injures the Lung (Fei). The combination of Imperatae Rhizoma (Mao Gen, Cogongrass Rhizome) and pig lung skillfully merges the herb’s heat-clearing action with the food’s tonifying effect, embodying the core TCM principle of “medicinal and culinary homology” (medicine and food share the same origin).

In Guangdong, Guangxi, and other regions, during seasonal transitions and influenza-prone periods, many families prepare this soup to prevent respiratory diseases. Its enduring popularity has made it a widely circulated folk wisdom for health preservation.

Efficacy of Medicinal Diet

Clear heat, moisten the Lung, relieve cough, and transform phlegm.

Mao-Gen-Pig-Lung Soup (Bai Mao Gen Zhu Fei Tang) is most notable for its effects of clearing heat, moistening the Lung, stopping cough, and transforming phlegm. Bai Mao Gen (Imperatae Rhizoma, Common White Rush) is cold in nature and sweet in taste, adept at clearing and discharging heat from the Lung and Stomach, as well as cooling the Blood and promoting urination. Zhu Fei (Pig Lung) can tonify the Lung, moisten dryness, stop cough, and calm panting. When used together, they have a favorable relieving effect on patterns such as Lung-heat cough, dry cough with scant sputum, and sputum with blood-streaked expectoration. Modern nutritional research has found that pig lung is rich in collagen and various amino acids, which can nourish the respiratory tract mucosa and enhance Lung immunity.

Induce diuresis to reduce edema, cool blood to stop bleeding.

The active components such as coixol and imperanene found in *Imperatae rhizoma* (Bai Mao Gen) have significant diuretic effects, helping the body eliminate excess water and metabolic waste. This is particularly effective for conditions like dysuria and edema caused by Damp-Heat. Additionally, *Imperatae rhizoma* can cool the blood and stop bleeding, providing auxiliary therapeutic effects for bleeding symptoms such as epistaxis, hemoptysis, and hematuria due to Blood-Heat causing reckless movement.

The Role of Traditional Chinese Medicine

From the perspective of Traditional Chinese Medicine theory, Imperata Rhizome and Pig Lung Soup (Mao Gen Zhu Fei Tang) enters the Lung (LU), Stomach (ST), and Bladder (BL) meridians. Imperata Rhizome (Bai Mao Gen, *Imperata cylindrica*) is sweet in flavor and cold in nature. Entering the Lung meridian, it clears Lung Heat and stops cough with counterflow qi; entering the Stomach meridian, it engenders fluids, relieves thirst, and eliminates vexing heat; entering the Bladder meridian, it promotes diuresis and guides heat downward. Pig lung is sweet in flavor and neutral in nature. It exclusively enters the Lung meridian, and can tonify Lung deficiency, moisten Lung dryness, and stop cough. The two complement each other: one clears and the other tonifies, one drains and the other moistens. Thus Lung Heat is cleared while Lung Yin is nourished, treating both the root and branch.

TCM posits that the “lung is a delicate organ, preferring moisture and disliking dryness.” When externally invaded by wind-heat or dryness pathogens, lung qi readily becomes constrained and transforms into heat, resulting in symptoms such as cough, dry throat, and yellow sputum. The Soup of Imperatae Rhizoma and Pig Lung (Maogen Zhufei Tang) utilizes the heat-clearing and diuretic action of Imperatae Rhizoma (cogongrass rhizome) to guide the heat pathogen out via urination, while the moistening and tonic properties of pig lung help repair damaged lung collaterals. This achieves the therapeutic effect of “expelling pathogens without harming the right (healthy qi).” This medicinal food is particularly suited for use when TCM pattern differentiation identifies “lung heat congestion” (Fei Re Yong Sheng) or “dryness-heat damaging the lung” (Zao Re Shang Fei).

Target Population

Imperatae Rhizome and Pig Lung Soup is particularly suitable for individuals with lung heat cough, sore throat, and dry mouth and throat, especially those who smoke long-term, work in dusty environments, or are teachers and others who frequently use their voice. For symptoms such as recurrent cough due to lung heat, yellow and thick phlegm that is difficult to expectorate, consuming this soup can provide significant relief.

Furthermore, for individuals with chronic bronchitis, bronchiectasis, mild pneumonia, and other respiratory conditions, consuming an appropriate amount of Mao Gen Zhu Fei Tang (Imperatae Rhizoma [Lalang Grass Rhizome] and Pig Lung Soup) during the stable phase can help clear residual heat from the Lung and repair damaged tissues. For those who tend to develop internal heat (shang huo) in spring, presenting with epistaxis or gingival bleeding, this soup also exerts the actions of cooling blood and stopping bleeding. It is equally suitable for patients with difficult urination (lin syndrome) and mild edema.

Contraindications

People with spleen-stomach deficiency cold and loose stools should avoid consuming Imperata Root and Pig Lung Soup, as Imperata Root (Bái Máo Gēn) is cold in nature and may impair spleen-stomach yang qi, aggravating diarrhea and cold abdominal pain. If such individuals still need to consume it, 3 to 5 slices of fresh ginger (Shēng Jiāng) may be added to the soup to neutralize the cold nature, though caution regarding dosage remains necessary.

Pregnant and breastfeeding women should use *Imperata cylindrica* (cogongrass rhizome) with caution, as its diuretic effect may affect electrolyte balance in the body. It is also not suitable for elderly and children with an extremely weak constitution and yang deficiency pattern, as well as individuals allergic to pig lung. Additionally, those taking warming tonic Chinese herbs or Western medications should consume it under a doctor’s guidance to avoid potential drug interactions that could affect therapeutic efficacy.

Ingredient formula ratio

The following is the standard formula and proportions for Mao Gen Zhu Fei Tang (Cogongrass and Pork Lung Soup, serves 4–5 people): Fresh Imperata cylindrica (cogongrass root) 150 g (if fresh is unavailable, substitute with 50 g dried Imperata cylindrica); pork lung 1 piece (approx. 500–600 g); honeyed Fructus Jujubae (honey dates) 3 pieces (approx. 30 g); Citri Reticulatae Pericarpium (tangerine peel) 1 small segment (approx. 3 g); Zingiber officinale (fresh ginger) 2 slices (approx. 6 g); table salt, to taste (approx. 3 g, added at the end for seasoning).

Fresh, thick, and white Imperatae Rhizoma (cogongrass rhizome) is preferred; for pig lung, choose a healthy one with a light pink color and no bruising or damage. Honey dates and Citri Reticulatae Pericarpium (tangerine peel) not only enhance the soup’s sweet flavor but also help remove the fishy taste of the pig lung. Additionally, tangerine peel has the effect of regulating qi and strengthening the spleen (理气健脾), which can balance the cold nature of cogongrass rhizome. The proportions of all ingredients can be slightly adjusted according to individual constitution and taste, but the amount of cogongrass rhizome should not be excessive.

Cooking method

Step 1: Prepare the pig lung. Attach the trachea of the pig lung to a faucet and repeatedly flush it with water until the lung expands, turns pale, and all blood is completely rinsed out. Then, cut the pig lung into cubes of about 3 cm, blanch them in boiling water for 3 to 5 minutes. Remove and rinse thoroughly with cold water, then set aside. This step is crucial for effectively removing the fishy odor and impurities from the pig lung.

Step 2: Prepare the herbs. Fresh Imperata cylindrica (Cogongrass rhizome) is washed and cut into approximately 4 cm long sections. Dried Imperata cylindrica is soaked in clean water for 20 minutes in advance. Dried red dates (Ziziphus jujuba) are washed and pitted. Tangerine peel (Citri Reticulatae Pericarpium) is softened in warm water, then the inner white pith is scraped off. Fresh ginger (Zingiber officinale) is washed and sliced.

Step 3: Simmer the soup. Place the prepared pig lung pieces, Imperatae Rhizoma (cogongrass rhizome), honeyed jujubes, Citri Reticulatae Pericarpium (tangerine peel), and fresh ginger slices into a clay pot or soup pot. Add sufficient water (approximately 2500 to 3000 ml). Bring to a boil over high heat, skim off any foam, then reduce to low heat and simmer for 1.5 to 2 hours. During simmering, avoid lifting the lid frequently to prevent loss of aroma.

Step 4: Season and finish cooking. Once the pig’s lung is tender and the soup turns a light yellow color, add an appropriate amount of table salt to season. Note: Add the salt only at the very end, just before turning off the heat. Adding salt too early will cause the lung meat to become tough. After turning off the heat, let the soup rest covered for another 5 to 10 minutes to allow the flavors to meld further. When serving the soup, you may remove the pig’s lung and dip it in a small amount of soy sauce for a distinctive flavor.

Tips for Consumption

1. Imperatae Rhizoma (Bai Mao Gen) and Pig Lung Soup should be consumed warm 1 to 2 hours after meals, with each serving of 150 to 200 ml. A continuous intake of 3 to 5 days constitutes one treatment course. It is not recommended to take on an empty stomach, as the cold nature of Imperatae Rhizoma (Bai Mao Gen) may irritate the gastrointestinal tract.

2. This soup has a cool nature, and the best seasons for consumption are spring and autumn, especially during the high-incidence period of wind-heat common cold in spring and when dryness pathogen prevails in autumn. It can be consumed in moderation in summer, but those with a cold body pattern in winter should reduce the frequency of consumption or combine it with warming ingredients such as ginger (Zingiber officinale) and red dates (Ziziphus jujuba).

3. The leftover soup can be stored in the refrigerator for 1 to 2 days, and should be brought to a full boil before consuming again. However, note that pork lung should not be reheated repeatedly; it is best consumed within 24 hours. If the soup develops an off smell or becomes cloudy, it should be discarded immediately and not consumed.