Deep in the Han Yangling Mausoleum, north of Xi’an, China, plant material, thousands of years old, was discovered. Though the material was excavated in the 1990s, it has taken until now to confirm that the material is tea.
Scientists confirmed the origin of the material found in Emperor Jingdi’s tomb by testing the biomolecular compounds, radiocarbon dating and calcium phytoliths in the sample. Phytoliths are microscopic pieces of cacium oxalate that form in plant cells and remain after decay. Caffeine and theanine content were part of the analysis. Researchers noted that because the remains contained only buds and small leaves, it was originally “fine plucked” tea.
“The sample contains a mixture of tea, barley (Hordeum vulgare, Poaceae) and other plants. Therefore, it is likely that tea buds and/or leaves were consumed in a form similar to traditionally-prepared butter tea, in which tea is mixed with salt, tsampa (roasted barley flour) and/or ginger in the cold mountain areas of central Asia. Of course, methods of brewing and consuming tea varied from culture to culture along the Silk Road,” stated Houyuan Lu’s article in Nature’s Scientific Reports.
Xi’an sits at the far eastern end of the original Silk Road. These samples confirm that the Han Chinese and Tibetans were trading tea back at 200 BCE.
The oldest samples of tea cultivation in China date to Neolithic times. In 2004 Chinese archaeologists digging in the Tianluo Mountains near Ningbo, in Zhejiang province traced the origin of tea to around 3,000 years before the Egyptians constructed the first pyramids.