In the golden autumn of September, after four months of cultivation and care by villagers, the 500-acre pepper plantation in Geyi Township, Taijiang County, Guizhou Province, finally reached maturity and welcomed the harvest season. With plump, vibrant peppers hanging from branches, more than 20 villagers from nearby areas gathered at 8 AM in the fields, skillfully picking and bagging the peppers. Each villager could harvest about 300 pounds of peppers per day, earning 120 yuan in income. At 5 PM, villagers would remove the stems from the concentrated harvest as required, and within 30 minutes, these fresh peppers would be transported to the Miaomiao Food factory located in Taijiang County, Qiandongnan, Guizhou.

Besides seasonal employment opportunities for villagers, pepper growers also benefit from Miaomiao Food's operations. Taijiang County has a long history of growing and consuming peppers. The local soil is deep and rich in organic matter, combined with suitable light and temperature differences. The Erjingtiao peppers produced in the hills are long, red in color, with pure and refreshing spiciness, suitable for both fresh and dried use. Since the area doesn't produce salt, local households have traditionally made acid soup using fresh tomatoes, peppers, and other ingredients.

However, even with such high consumption demand, farmers' income from pepper cultivation remained unstable in the past. "Previously, farmers had a difficult time selling peppers: they would pick peppers on the first day and had to go to Kaili City to set up stalls the next day, with extremely unstable sales. Due to concentrated pepper production, peppers might sell for 2 yuan in the morning, 1.8 yuan at noon, and only 1.6 yuan in the evening. Market price fluctuations were significant, making it difficult to guarantee farmers' income," explained an agricultural department worker from Geyi Township.

Now, farmers no longer worry about sales channels, selling their peppers to Miaomiao Food through contract farming. Under Miaomiao Food's order-based purchasing model, farmers can achieve income of over 4,000 yuan per acre. This transformation is the result of collaborative efforts between Taijiang County government, GUOQUAN Food, and the Institute of Food Science and Technology under the Chinese Academy of Agricultural Sciences (CAAS) in promoting rural revitalization, bringing unprecedented development opportunities to the traditional acid soup industry.

**"Customized" Superior Bacterial Communities**

Turning back to December 2021, the CAAS assistance team, under relevant department guidance, conducted science and technology assistance work in Taijiang County, Qiandongnan Miao and Dong Autonomous Prefecture, Guizhou. However, in the early stages of assistance, team members were also confused about how to complete this assistance work.

Li Shuying, a researcher at CAAS and technical director of Miaomiao Acid Soup Food, admitted that past poverty alleviation efforts often focused on primary industry assistance, helping people increase income through increased production from farming and breeding. However, Guizhou has distinctive regional characteristics with limited land area, making land resources a constraining factor for industrial development.

In their confusion, Miao acid soup, found throughout Guizhou's streets and alleys, entered the assistance team's vision. Miao acid soup has deep historical heritage in Kaili. Historically, when Miao ancestors migrated from the Central Plains to this area, facing the challenge of salt shortage, they cleverly "replaced salt with acid," using sourness to stimulate appetite, aid digestion, and promote metabolism. Therefore, the local saying goes, "Without eating sour food for three days, walking becomes unsteady."

In 2021, Miao acid soup production techniques were listed in the National Intangible Cultural Heritage Registry, Kaili red acid soup was recognized as a National Geographical Indication Product, and "Kaili Acid Soup" was approved by the National Intellectual Property Office as a public collective trademark.

Thus, acid soup, with both cultural heritage and good consumer foundation, became the key focus of Li Shuying's assistance work. However, unlike highly standardized cuisines such as Hunan and Sichuan cuisine, acid soup is divided into "raw acid" and "cooked acid," with their flavor profiles heavily dependent on fermentation processes, stir-frying techniques, and local ingredients. For example, after raw acid fermentation is complete, it must be stir-fried to become an edible hot pot base. The acid stir-frying process requires high standards for heat control, cookware, and chef experience, resulting in different acid soup flavors at every household, making complete standardization very difficult.

The CAAS assistance team, which had been dedicated to microbial fermentation research, thought of their unique bacterial community domestication technology. In late December 2021, researcher Li Shuying led her team, with local government support, to conduct a week-long deep dive into 18 villages across 5 townships in Taijiang County, collecting 26 samples of homemade acid soup. Using molecular biology techniques to analyze the bacterial community structure of Guizhou acid soup, they successfully isolated 463 bacterial strains.

Subsequently, to enable commercial implementation of acid soup products, researcher Li Shuying made significant efforts in product standardization, safety, and production cycle optimization. "Through bacterial community domestication technology, the CAAS assistance team not only maintained flavor authenticity while completely eliminating potential pathogenic bacteria, but also shortened the traditional 3-12 month natural fermentation cycle to 7 days," Li Shuying explained.

Achieving this was not easy. Li Shuying revealed that to maintain flavor, her team used pH, acidity, spiciness, flavor, nutrition, and lactic acid bacteria functionality as indicators, ultimately selecting safe and healthy acid soup products that retained authentic Miao village flavors while being rich in various organic acids and amino acids.

Furthermore, domesticating selected core fermentation bacteria to become more stable, healthy, and suitable for industrial production proved even more challenging. "Traditional acid soup has high salt content. In experiments, we repeatedly reduced salt content, allowing core fermentation bacteria to survive in low-salt environments, achieving healthy low-salt effects. As fermentation progresses, acid soup forms an acidic environment. To increase bacterial acid production capacity and tolerance, we repeatedly increased acidity in experiments, allowing fermentation bacteria to adapt, achieving better nutritional and flavor effects," Li Shuying explained.

After successful acid soup patent bacterial community domestication, how to transition from laboratory to enterprise for formal commercialization became another challenge. Li Shuying admitted that she and relevant leaders from Taijiang County approached many companies hoping to achieve cooperation for commercial implementation, but due to various reasons, they were unable to proceed. It wasn't until 2024, promoted by the Central Organization Department's Taijiang Poverty Alleviation Working Group, the Ministry of Agriculture and Rural Affairs, and Taijiang County government, that CAAS partnered with GUOQUAN Food to jointly establish Miaomiao Acid Soup Food Co., Ltd. in Taijiang County, finally implementing this industrial agriculture assistance project.

**Technology Empowering Intangible Cultural Heritage Crafts**

The key to this bowl of acid soup carrying "intangible cultural heritage" techniques reaching from Miao villages to the entire country lies not only in fermentation technology breakthroughs, but also in customized modern acid soup production lines.

The white factory building covering 20,000 square meters represents an intelligent acid soup production line that the GUOQUAN team built in Guizhou's mountains over seven months. Unlike traditional earthenware jar methods that rely on worker experience, lengthy cycles, and quality fluctuations of traditional acid soup crafts, everything here becomes standardized, visualized, and scalable for replication.

Miaomiao Acid Soup Food staff revealed that in the acid soup production chain of "raw materials - selection - cleaning - crushing - mixing - sterilization - fermentation - stir-frying - packaging," each step has corresponding standards. The research team also designed stepped temperature control and dynamic monitoring processes for flavor enhancement, achieving visible and controllable fermentation processes, improving flavor stability by 12 times.

Specifically, Miaomiao Food signs raw material procurement agreements with farmers across all 9 townships (streets) in Taijiang County for tomatoes, peppers, ginger, garlic, and other materials, providing stable, high-quality raw materials for the enterprise. After fresh-picked raw materials are transported to the factory, workers first screen them. Taking Maolaguo (a local tomato variety) as an example, workers select fruits with appropriate ripeness, no pest damage, and no breakage, ensuring raw material quality meets production requirements.

After screening, raw materials enter the cleaning phase. In the blending and sterilization workshop, workers clean packaged fresh peppers, Maolaguo, ginger, and other raw materials, removing surface soil, impurities, and pesticide residues. Cleaned raw materials undergo slicing and crushing through production lines, making them more suitable for subsequent fermentation.

Sliced, crushed, and pulped raw materials are injected through sealed pipelines into large sterilization tanks. Here, raw materials undergo thorough sterilization to avoid residual bacteria affecting subsequent fermentation. The sterilization process uses high temperature and pressure methods, ensuring complete elimination of microorganisms in raw materials and guaranteeing fermentation environment purity.

Sterilized raw materials are transported through pipelines to the fermentation workshop, where six 22-ton medical-grade stainless steel fermentation tanks are arranged. Sterilized raw materials are mixed here with directionally domesticated bacterial strains from agricultural science experts, beginning a 7-day fermentation journey.

Advanced online monitoring systems are also equipped here, with screens displaying real-time temperature, acidity, dissolved oxygen, and other key parameters. Staff can adjust fermentation conditions in real-time based on this data, ensuring optimal fermentation conditions throughout the process.

After fermentation, acid soup enters the stir-frying workshop through pipelines. Here, acid soup is stir-fried according to different product formulations, adjusting flavor and taste. Finally, stir-fried acid soup enters the sterile hot-filling area. Miaomiao Acid Soup Food staff explained that entering this area requires secondary clothing changes, and equipment cleaning and disinfection follow unified SOPs (Standard Operating Procedures). Through sterile filling and 82°C-85°C hot-filling processes, products achieve zero preservatives, zero additives, zero flavoring, zero coloring, and zero acetic acid while obtaining longer shelf life.

Miaomiao Acid Soup Food General Manager Yu Wenxin introduced that the Miaomiao Food production line took only several months from project initiation to completion of construction and debugging, currently achieving annual production capacity of 12,000 tons of acid soup base.

When traditional Qiandongnan Miao village small stoves requiring clay pot natural fermentation transition to intelligent digital factories, modern agricultural technology is upgrading traditional intangible cultural heritage cuisine.

**"Acid Soup" Industry Transformation**

As a culinary business card of Guizhou Province, the Guizhou "acid soup" industry is experiencing transformation. In recent years, acid soup cuisine can be seen everywhere on Guizhou's streets and alleys, being loved by diners nationwide through specialties like acid soup hot pot, acid soup fish, acid soup beef, acid soup pig's feet, sour and spicy hot pot, Duoduo noodles, and acid soup rice noodles.

On the Douyin platform, topics related to "Guizhou Acid Soup," "Guizhou Acid Soup Hot Pot," and "Guizhou Red Acid Soup" have garnered 260 million, 440 million, and 160 million views respectively. As acid soup popularity continues rising, it's becoming one of the most watched subdivision categories in the restaurant industry.

According to official data from Qiandongnan Prefecture, the prefecture's acid soup industry total output value exceeded 2.5 billion yuan in 2024, with annual acid soup product capacity reaching 160,000 tons. Even many hot pot brands like Haidilao, Banu Maodu Hot Pot, and Zhu Guangyu Hot Pot Restaurant have launched acid soup hot pot bases.

Against this background, Guizhou acid soup has become an important category in hot pot dining. The "China Hot Pot Business Development Report 2024" shows that in hot pot base flavor popularity rankings, acid soup bases rank second, just behind beef tallow bases, becoming a strong dark horse in hot pot consumption.

Indeed, many media outlets and institutions have published reports in recent years calling it the next trend and a new model for regional cuisine nationalization. They believe that in the coming years, the acid soup market is poised for explosive growth.

On one hand, with improved living standards and popularization of healthy eating concepts, people pay more attention to healthy foods, and acid soup naturally has health advantages. Related nutrition experts also indicate that lactic acid bacteria in acid soup help intestinal health, while peppers and tomatoes rich in vitamin C can enhance immunity. In hot weather, acid soup can both stimulate appetite and replenish electrolytes, making it a "natural heat-relieving drink."

On the other hand, unlike previous difficulties in standardizing acid soup categories, companies like Miaomiao Food have now achieved acid soup production standardization, making acid soup industry implementation more convenient.

Yu Wenxin also revealed that Miaomiao Food, committed to making healthy good acid soup, is working to build "Guizhou Acid Soup" into a nationally and even globally famous culinary brand. He stated that Miaomiao Food not only deeply integrates with GUOQUAN channels but has also reached customized base material agreements with multiple well-known restaurant enterprises. Additionally, they are connecting with Vietnamese markets.

The transformation of acid soup is not only a story of industrial upgrading but also a microcosm of Chinese agricultural technology innovation empowering rural revitalization. In fact, this industrial agriculture assistance and support project has already achieved preliminary agricultural assistance goals beyond commercial success.

Currently, the factory has absorbed over 70 laborers from surrounding villages and towns near Taipan. Beyond direct positions, Miaomiao Food also promotes farmer connection and support through raw material procurement and other methods, promoting seasonal employment for farmers.

As the core raw material supply area, Geyi Township, during planting, maintenance, and harvesting peak periods, the pepper base uses an average of 30 workers daily, driving over 2,000 seasonal employment instances and helping over 40 villagers achieve employment income increases of over 5,000 yuan.

In the future, Miaomiao Food's upstream raw material planting operations, through acid soup raw material procurement supply and order-based farmer connection and support, may bring more surprises to local employment and income increases.

As the agricultural department worker from Geyi Township stated, the order planting model can effectively eliminate farmers' sales concerns. More villagers will return to plant peppers next year "because they've already seen others make money this year."