On the afternoon of February 10, at the Wenluo Industrial Park in Lingshui Li Autonomous County, trucks loaded with zao bai cu (vinegar lees) products departed one after another from the facility of Hainan Yixiaoxian Technology Co., Ltd. (hereinafter referred to as Yixiaoxian). "As the Spring Festival approaches, our order volume has surged 200% beyond expectations," said Huang Zhenhua, general manager of the company. Since the zao bai cu production base commenced operations last October, he has been extremely busy. "We are not only focused on shipping orders but also sometimes host multiple business negotiation teams in a single day." Similarly stretched thin is Zeng Weikang, assistant to the chairman of Ding'an Awo'o Food Technology Co., Ltd. "Since early February, the second-phase factory of 'Puqian Sanpo' has been working overtime to prepare for trial production," he noted. After overseeing equipment adjustments, Zeng hurried from Ding'an to Wenchang to manage the company's newly opened Puqian Zao Bai Cu Cultural Experience Hall, which is currently in a trial operation phase.
Racing to fulfill orders, expanding production capacity, and opening new stores—these activities highlight the vigorous development momentum of Hainan's zao bai cu industry. Data from the Hainan Provincial Task Force for Promoting High-Quality Development of the Zao Bai Cu Industry (hereinafter referred to as the Provincial Task Force) show that by the end of 2025, the province had 24 zao bai cu production enterprises, with an annual output value nearing 90 million yuan and an annual production capacity of 12,600 tons. Compared to July 2025, these figures represent growth rates of 41%, 45%, and 50%, respectively. In just half a year, how has this "Hainan-style sour soup" generated such remarkable energy?
Two forces—market demand and government support—have synergistically driven the industry's rapid expansion. On a weekend afternoon, well past the typical lunch hour, a zao bai cu hot pot restaurant in Haikou Bay remained bustling with customers. "We intentionally came during an off-peak time, but it's still so crowded," said a diner, Ms. Wu, waiting outside. She and her friends visit the restaurant almost every two weeks. Many share her enthusiasm for the dish. On a popular review website, three of the top ten restaurants in Haikou by food sales feature zao bai cu as their main product.
"As early as 2018, we opened several zao bai cu hot pot outlets in Haikou and Sanya," recalled Huang Zhenhua. Although business has been consistently good, the company previously relied on third-party suppliers for its hot pot base, which led to inconsistent quality. This gap between demand and supply inspired Huang to venture into upstream production. Meanwhile, the brand "Puqian Sanpo," which established its factory in 2021, also sought new growth opportunities. "In recent years, we improved our techniques to overcome preservation and transportation challenges, enabling our products to be sold abroad. However, limited production capacity made it difficult to handle large orders," explained Zeng Weikang. To achieve scale, the company began constructing a second-phase factory in June 2024, with a designed annual output of 20,000 tons—nearly five times that of the first phase.
As both new and established players expanded their market presence, the government provided additional impetus. In July of last year, the Hainan Provincial Government held a special meeting to discuss measures for advancing the high-quality development of the zao bai cu industry. Concurrently, the Provincial Market Regulation Bureau and over twenty other units jointly established the Provincial Task Force. Provincial and local governments subsequently formulated implementation plans to support the industry, rolling out a series of supportive policies that have accelerated its growth. "We received 5 million yuan in provincial subsidies, and market regulation departments have offered multiple on-site technical guidance sessions," Huang noted. He attributes the rapid completion and operation of Hainan's first fully transparent, automated zao bai cu production plant to such government efforts. "With counties like Ding'an, Wenchang, Haikou, and Lingshui relocating zao bai cu producers into industrial parks, several projects have either commenced production or are about to do so, forming an initial industrial cluster," added a representative from the Provincial Task Force.
The production line has undergone a "radical transformation," shifting from reliance on experience to data-driven processes. Two or three years ago, zao bai cu production in Hainan primarily depended on the expertise of seasoned masters using earthenware jars for natural fermentation. Timing for adding ingredients and fermentation duration were determined by intuition. Today, at Yixiaoxian's production base, the process looks截然不同. Inside the fully transparent visitor corridor, hundreds of fermentation tanks operate simultaneously in the raw fermentation workshop. Sensors at the bottom of each tank monitor temperature, humidity, and microbial activity in real time. "This data is uploaded to an intelligent control platform, allowing us to monitor each tank's status clearly—no longer relying on smell," Huang explained. By collaborating with academic institutions, the company has made breakthroughs in strain selection and achieved a balance between traditional flavor and standardized production through smart, precise control.
This shift from experience-based to data-driven production is echoed by other local producers like "Puqian Sanpo" and "Haidong Yongfang," which have also upgraded their production lines. "During this process, we formed technical support teams to offer policy advice and on-site guidance to enterprises," said Yin Xiaojing, deputy director of the Food Production Supervision Department at the Provincial Market Regulation Bureau. Over the past year, the bureau has provided quality diagnostics and assistance to 15 zao bai cu companies, identifying key quality issues and control points. Simultaneously, another breakthrough—from zero to one—has been made. For a long time, the lack of standards for zao bai cu production hindered industry regulation. On November 26, 2025, the issuance of the "Hainan Provincial Food Safety Local Standard for Zao Bai Cu" provided a unified, scientific basis for production, inspection, and supervision.
Standardization extends beyond the production floor. In the past year, the Provincial Task Force promoted the release of evaluation and management standards for zao bai cu catering businesses and initiated the development of a comprehensive standard system for the entire industry chain. This effort aims to establish a standardized,规范化 management framework spanning from raw materials to end products. "Recently, we also established a provincial-level technical expert committee for zao bai cu, inviting experts, including academicians from the Chinese Academy of Engineering, to provide intellectual support," Yin shared. The next step involves leading legislative research on the "Hainan Provincial Zao Bai Cu Industry Development Regulations" to further solidify institutional support for the industry's growth.
Cross-border integration under the "zao bai cu+" concept promotes sustained popularity. How many ways can a bowl of zao bai cu be enjoyed? Last July, at a long-table banquet in Puqian Town, Wenchang, creative pairings of the sour soup with various ingredients delighted diners. "Zao bai cu is more than just vinegar!" asserted Zhang Hanbing, head of Haidao Yongfang Zao Bai Cu. To reach a broader market, it is essential to challenge consumers' preconceptions. Today, many Hainan producers and restaurants have developed "zao bai cu+" product lines—such as zao bai cu seafood rice noodles, fruit beverages, and coconut milk Wenchang chicken—tailored to diverse dining scenarios and modern tastes.
The "plus" in "zao bai cu+" extends beyond product variety. "In addition to investing in cultural experience halls, we have sponsored events like the thousand-person zao bai cu hot pot banquet and the 'Qiong Super League' sports event," Zeng Weikang highlighted. These cross-sector initiatives not only convert event attendance into brand growth but also create new consumption settings for Hainan zao bai cu. Last year, sales of "Puqian Sanpo" zao bai cu products increased by over 40% year-on-year. However, even a good product needs visibility. Over the past year, Hainan has conducted promotional campaigns, introducing zao bai cu dishes to approximately 600 restaurants in cities like Beijing, Shanghai, and Shenzhen, while expanding e-commerce coverage to more than 30 cities, allowing the "sour aroma of Hainan" to spread farther.
"To further enhance the brand influence of zao bai cu, we introduced a management measure for the 'Hainan Zao Bai Cu' regional public brand and guided local governments and enterprises to apply for geographical indication trademarks and related patents," Yin detailed. Last year, Hainan saw five invention patent applications, ten utility model patents, and five design patents related to zao bai cu, gradually building a dual-drive model of "regional public brand + geographical indication trademarks." Despite achieving scale, quality improvements, and stronger branding, challenges remain in Hainan's zao bai cu industrialization journey. "For instance, there is insufficient coordination between upstream and downstream sectors, and a lack of leading enterprises and well-known brands," acknowledged the Provincial Task Force representative. This year, the province will increase policy support in funding, enterprise cultivation, park development, and brand enhancement. Plans include assisting companies in technological upgrades, establishing three or more raw material production bases, and creating a cultural IP for Hainan zao bai cu to foster integrated development across primary, secondary, and tertiary industries for long-term success.