On November 4, according to the Minbei Daily, Professor Sun Yun's team from Fujian Agriculture and Forestry University, together with Yanba Tea Industry from Wuyishan, recently published their latest research findings on LED light withering technology in the renowned food science journal "Food Chemistry: X".
This study is the first to systematically reveal how artificial light sources can effectively replace sun-drying by regulating the transformation of the internal chemical substances in oolong tea, thus ensuring the stable production of high-quality oolong tea even in cloudy or rainy weather.
Image source: Minbei Daily
It is understood that the production of Wuyi rock tea, especially the crucial "withering" process, has long been a challenge. However, the spring tea season often coincides with the rainy season, and the high-altitude tea-growing areas are shrouded in mist year-round, which often prevents the tea leaves from obtaining sufficient and suitable sunlight for withering, thus affecting the quality of the tea.
Faced with this common challenge in the industry, Professor Sun Yun's team from Fujian Agriculture and Forestry University collaborated with Yanba Tea Industry to combine scientific research with tea-making practice, and jointly explore the innovative application of "light withering and carving technology".
The research team used three representative oolong teas—"Chunlan," "Shuixian," and "Daphne"—as research subjects. They employed a multi-wavelength (380-780nm) LED combined light source (6000lx intensity) to simulate sunlight withering, with traditional methods serving as a control. Combining sensory evaluation, tea liquor color difference analysis, electronic tongue detection, and broadly targeted metabolomics techniques, they systematically analyzed the impact mechanism of LED light withering on the non-volatile metabolites of oolong tea.
To further explore the mechanism of quality improvement, the research team used a broad-targeted metabolomics approach for analysis. The results showed that LED photo-sculpting can promote the conversion of bitter substances such as flavonoids, alkaloids, and bitter amino acids, while coordinating the ratio of umami and sweet substances, thus forming a mellow and full-bodied flavor profile.
LED light withering technology not only solves the weather-related challenges of traditional oolong tea production, but also provides a new technological path for the entire tea industry to cope with natural challenges and achieve stable production. (Source: Minbei Daily)
