Newly domesticated wild tea cultivar offers unique beverage possibilities that promote forest conservation while representing the specific flavors and aromas of Taiwan. Photo credit: Tea and Beverage Research Station (TBRS) of Taiwan’s Ministry of Agriculture
The Tea and Beverage Research Station (TBRS) of Taiwan’s Ministry of Agriculture recently announced breakthroughs in high-value processing of a newly domesticated wild tea species native to Taiwan, known as Tai Cha 24, or Shan Yun [山蘊]. Using special tea processing techniques, TBRS successfully produced a batch of GABA oolong tea with higher concentrations of GABA and L-theanine than other tea products currently on the market, heralding new possibilities for Taiwan’s functional beverage industry and under-forest economy.
A Rare and Protected Tea Species Joins the Under-Forest Economy
Endemic to Taiwan, Camellia formosensis is a wild tea species classified as near-threatened due to its rarity. It resembles Camellia sinensis but grows to heights of up to ten meters, and its habitat is scattered throughout Taiwan’s central, southern, and eastern mountains, at elevations ranging from 600 to 1500 meters. TBRS underwent nineteen years of selective breeding to develop wild Taiwanese tea varietals into the Tai Cha 24 cultivar, which exhibits heartier resistance to pests and diseases, making it suitable for organic farming. Also known as Shan Yun [山蘊], Tai Cha 24 is currently the only tea cultivar developed by TBRS that exclusively contains C. formosensis genetics.
In 2019, the Forestry and Conservation Agency of Taiwan’s Ministry of Agriculture began promoting an under-forest economic policy model that uses forest zones without disrupting their ecosystems. C. formosensis was officially added to the list of under-forest economic products in December 2021. In addition to helping protect the environment and defending biodiversity, this policy grants C. formosensis a crucial role in the local economy and could potentially provide a blueprint for similar conservation efforts in the future.
TBRS Director Tsung-chen Su says that Tai Cha 24 holds profound significance for research and species conservation, and that the newly developed high-value GABA processing demonstrates the potential of C. formosensis varietals to produce premium products in the health beverage industry.
Experiments using GABA oolong processing techniques for Tai Cha 24 have consistently created high-quality tea that meets the standards for use in functional beverages.
From Species Conservation to the High-Value Market
According to TBRS, tea leaves are naturally rich in antioxidants and beneficial compounds that help to regulate metabolism and relieve stress. Many studies suggest that L-theanine heightens calmness and focus, while GABA, a compound that forms through anaerobic fermentation, can lower stress levels and aid sleep. A special TBRS research team developed GABA oolong processing to open up new market possibilities for C. formosensis, which is usually made into green or black tea.
The new process uses alternating rounds of anaerobic and aerobic steps to transform Tai Cha 24 into GABA oolong tea, which contains a higher concentration of functional compounds. The resulting GABA oolong tea contains 249mg of GABA per 100g of tea, exceeding the 150mg/100g threshold required for GABA tea products. L-theanine levels also reach 11.45mg/g, surpassing L-theanine levels of more mainstream cultivars and currently available GABA teas.
According to TBRS, GABA oolong teas made using Tai Cha 24 also have unique woody and mushroom notes that set them apart from other oolong teas, as well as a mellow sweetness with hints of sugarcane and roasted chestnuts. Gas chromatography–mass spectrometry (GC-MS) analysis has successfully identified aromatic molecules, which may serve as a basis for future quality control.
The Forestry and Conservation Agency now classifies Tai Cha 24 as an under-forest crop. TBRS will continue to research the functional properties of C. formosensis and refine tea-making techniques to further promote development of the under-forest economy, opening up new possibilities for high-value products in the functional beverages industry while providing a major boost to species conservation and creating a unique, inimitable product representing Taiwanese tea in the international market.