Why Guizhou and Sour Soup are Inseparable | Book Recommendations & Livestream Preview

Foodthink’s Perspective

What follows is an excerpt from the chapter on Guizhou sour soup in the new book *Fermenting China: Yunnan and Guizhou*, provided with the author’s permission.

In Guizhou, the most poignant sense of nostalgia is undoubtedly found in a spoonful of spicy, refreshing sour soup. Sour soup is found throughout the province, and in Southeast Guizhou, it is the indispensable protagonist of the local dining table. “Three days without sour, and your steps lose their strength.” This local proverb reflects the conviction of the Guizhou people: life is not complete without sourness. Sour soup is a staple of daily meals and is essential during important festivals, such as the Eating New Festival, the Dragon Boat Festival, the Fishing Festival, and the Miao New Year… during every joyful celebration, sour soup dishes serve as the fermented thread that binds people together.

Guizhou’s sour soups are divided into different categories: White Sour Soup, known colloquially as rice sour soup, uses rice or noodle water as its base and is fermented by microorganisms such as acetic acid bacteria, lactic acid bacteria, and yeast; Red Sour Soup is primarily fermented from ingredients such as tomatoes, red chillies, and glutinous rice. Red sour soup made from tomatoes is called Tomato Red Sour Soup, while that made from chillies is Chilli Red Sour Soup; in some regions, the two are fermented separately and then mixed for a second round of fermentation. Although the ingredients differ, Red Sour Soup, like White Sour Soup, is produced through the mixed fermentation of various microorganisms—primarily lactic acid bacteria, yeast, and acetic acid bacteria—all of which ferment in an anaerobic environment.

Why did sour soup appear in Guizhou? Why does it possess such an enduring vitality here? To answer this, one must look back at the history of the development and migration of the Miao people. In the ancient era of Yao, Shun, and Yu, the Miao lived in the middle and lower reaches of the Yellow River. Following military defeats, they migrated continuously west and south to the Jianghan Plain. After a period of recovery and growth in the Jing-Chu region, the Miao rose in strength. Viewing them as a threat, the Zhou Dynasty’s King Xuan ordered Fang Shu to “campaign against the Man south”. During the Warring States period, Wu Qi used military force to “annex the Man and Yue in the south”. Repeatedly suppressed, the Miao ancestors were eventually forced into their most significant ethnic migration, moving south along the Wuling Mountains into uninhabited territories. They traversed thorn-choked mountain paths and sheer cliffs, eventually entering the Yunnan-Guizhou Plateau. In the Miao migration song “Crossing Mountains and Waters” from Southeast Guizhou, it is sung: “Through a thousand hardships, through ten thousand bitters. Migrated to the west, to create a good life.”

These Miao ancestors lived successively in the Central Plains and the Jing-Chu region, and their culinary culture was undoubtedly inherited from the Central Plains generations of the pre-Qin period. The *Rites of Zhou* (specifically the section on the Official of the Heavens and the Master of Fermented Meats) already records many fermented seasonings and preserves, indicating that this was a common dietary habit at the time. When the Miao ancestors reached the mountains of Guizhou, the specific geography and climate made fermentation—as a technique for food processing and preservation—exceptionally important. It was the result of generations of Miao ancestors adapting to their natural environment to survive. Geographically, the Guizhou plateau is characterised by towering mountains and deep ravines. A lack of salt resources combined with blocked transport routes made the cost of importing salt extremely high, leaving the Miao regions of Guizhou in a chronic state of salt deficiency. Ordinary Miao families could only use farmed rice and wild vegetables to create sour foods, using acidity for seasoning as a substitute for salt. Climatically, Guizhou is situated on the Yunnan-Guizhou Plateau with a humid subtropical monsoon climate, characterised by heavy rainfall, limited sunshine, frequent overcast days, and high humidity. The organic acids in sour soup help to strengthen the spleen, stimulate the appetite, and clear internal heat during the summer.

Today, we can explain the fermentation of sour soup through scientific principles, but for the Miao ancestors who first arrived in the mountains of Guizhou, its creation may have been an accident. Miao ancient songs are the encyclopaedias of the Miao people, and the origins of many customs can be found within them. One such song praising the ancestors reveals the origin of White Sour Soup: in the story of the ancestor Jiang Yang creating the world amidst a great flood, Jiang Yang was bitten by his rival, Leigong. Jiang Yang’s son went to visit his injured father, bringing a bamboo tube filled with rice water. Because the journey was so long, the rice water had fermented and turned sour by the time he reached his father. However, touched by his son’s filial piety, Jiang Yang drank it anyway and found the taste pleasant. From then on, the Miao people began the generational habit of drinking White Sour Soup.

Although the ancient songs attribute the discovery of White Sour Soup to an accident by Jiang Yang’s son, in a Miao household, the making of sour soup is the standard by which the diligence and skill of the women are judged. On the hearth of every home in a Miao village, there is at least one sour soup jar used for brewing White Sour Soup. The family’s own glutinous rice is the foundation of their survival, and it also provides the base for White Sour Soup. The method is simple: rice water is boiled into a clear rice soup and then placed in a jar to ferment for three to five days. While the process is easy, the key lies in the water quality and temperature. Mountain spring water or clean stream water ensures the primary quality of the soup. Placing the jar on the hearth ensures that the daily heat from cooking aids the fermentation. The mountain climate is humid, and while the local microorganisms floating in the air are invisible, they are active, coexisting and thriving with these jars of sour soup; fermentation is generally complete within three days. Every time sour soup is scooped out, the utensil must be clean and oil-free, as lactic acid bacteria are the key to fermentation; poor care can lead to spoilage, ruining the flavour. When a family’s stock runs low, they might borrow a “sour soup mother” (a starter culture) from a neighbour to maintain the fermentation, strengthening community bonds in the process. This simple sour soup—clear, white, fragrant, mellow, and with a lingering aftertaste—transforms every day into a rich tapestry of flavours. Vegetables, tofu, beef, fresh fish, pig’s trotters… everything can go into a sour soup. Especially during the oppressive summer heat, a bowl of sour soup brings a familiar taste that instantly calms and restores the spirit. Radiating outwards from Southeast Guizhou, sour soup has become a vital key to Guizhou’s unique culinary culture. Each plot of land nourishes its own version of sour soup; though recipes vary slightly, whether among the Miao, Dong, Sui, Buyi, or even on Han Chinese tables in Guizhou, the rich acidity brought by sour soup is the absolute protagonist.

Culinary culture is the finest mirror of an era, and Guizhou’s sour soup has quietly evolved through the long river of history. How did White Sour Soup give rise to another star, Red Sour Soup? This is where tomatoes and chillies take centre stage. Tomatoes were introduced to China during the Ming dynasty, but for a long time, they were kept as ornamental plants. The *Qunfangpu* (Compendium of Fragrant Plants), published in 1621, records: “The foreign persimmon [tomato], also known as the June persimmon… its stem is like a mugwort, four to five feet high, leaves like wormwood, flowers like pomegranate… it comes from the West, hence the name.” From the late Qing dynasty to the Republican era, Chinese people began to learn how to eat tomatoes. During this time, attitudes varied across regions. Yunnan was a pioneer in adopting the tomato; the 1937 *Shiping County Annals* notes that people once mistakenly thought tomatoes were poisonous, but “in recent years they have become a favoured food”. For Guizhou, where a love for sour flavours is universal, the arrival of the tomato was a perfect match. The *Majian County Annals*, published in 1938, mentions a method of preserving tomatoes: “pickled in jars with salt, garlic, chillies, and sweet rice wine”. This likely refers to the now-famous Guizhou delicacy, “Red Sour Soup”. Chillies arrived in the late Ming dynasty, initially called *fanjiao*. They first appeared in the 1591 book *Zunsheng Bajian* (Eight Albums on the Art of Living) by Gao Lian of Hangzhou, who wrote: “The foreign pepper grows in clumps with white flowers and fruit resembling the head of a bald brush; spicy in taste and red in colour, it is most pleasing to the eye.” At the time, scholars and wealthy merchants in the Jiangnan region treated them as ornamental flowers. Meanwhile, due to their spicy nature, chillies were also used as herbal medicine. In the 18th century, chillies reached the southwest and were called *haijiao*. The 1721 *Sizhou Prefecture Annals* records their presence, noting they first served as a salt substitute before becoming a food staple. Once tomatoes and chillies officially entered the kitchen, the wonderful union of spicy and sour created Guizhou’s distinctive flavour profile. Thus, the ancient White Sour Soup evolved, and from the late Qing dynasty, Red Sour Soup began its own legend of flavour in Guizhou.

Unlike White Sour Soup, the production of Red Sour Soup is closely tied to local climatic conditions and harvest seasons. From September, red chillies and bird’s eye chillies ripen, marking the ideal time to make the soup. The finest Red Sour Soup is simmered from local maolaguo (wild tomatoes), which are fleshy, firm, and sufficiently tart. Combined with salt, wine lees, and chillies in a jar for natural fermentation, the lid can be opened after 10 to 15 days, releasing a rich, aromatic fragrance of fermented fruit. Though called a “sour soup”, the taste is not simply acidic; it is a complex, multi-layered sensory experience. It lacks the sharpness of fruit acids and the thinness of vinegar; instead, the sourness is like a long, steady breath—deep yet subtle—blending with the savoury richness of meat before settling in the stomach. In Guizhou, any dish featuring sour soup is incomplete without a dipping sauce made from *Mukangzi* oil, its true soulmate. *Mukangzi* oil, also known as mountain pepper oil, is a specialty aromatic. The fermented tomato juice and rice water create the thick, refreshing base of the sour soup fish, while the slightly pungent *Mukangzi* oil adds a rich and complete texture, forming a seamless flavour pairing.

*Fermented China: Yunnan and Guizhou*

*Click the cover to purchase this book

Written by Ma Junli and Liu Xinzheng

China Light Industry Press

Published August 2025

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