Study On Rare Earth Elements Of Wuyi Rock Tea In Fujian Province

Tea is one of the most traditional Chinese foods. As the birthplace of tea, China has a long and rich history of tea culture. With the improvement of people’s living standard, healthy tea is more favored by people in the modern society. Chinese tea has become an indispensable health and spiritual drink in social life. Therefore, the quality and safety problem of tea, such as excessive amount of pesticide residues, heavy metals, and the rare earth elements in tea, has drawn more attention.The paper focused on the quality and safety problems of the rare earth elements in tea. We studied the relationship between the relate rare earth elements and soil elements in Wuyi Rock Tea. Results showed that the rare earth elements had positive correlations with the total soil rare earth element in Wuyi Rock Tea. The application of fertilizer and content of rare earth elements in various fertilizers were also analyzed. We draw the conclusion that using mineral as raw material, for example, calcium superphosphate to obtain fertilizer, would result in higher amount of rare earth element than using compound fertilizer and foliar fertilizer. Using chemical integrity fertilizer, such as ammonium bicarbonate and urea, would result in least amount of rare earth element in Wuyi Rock Tea. Study on the tea growth of tea and fertilization also showed that the fertilizer had a certain positive correlation effects on rare earth content in tea. In this paper, we also analyzed the rare earth elements in the different maturity level of the tea leaves and the distribution of rare earth in different maturity level of rare earth tea. The results showed that apart from the crown, rare earth content in tea was also bound up with the tea leaf maturity level. As tea leaves grow mature, the more rare earth concentrates in the finished product tea, the higher the rare earth elements accumulate. In this paper, we further studied the leaching rate of rare earth elements in tea. The results showed that the leaching rate of rare earth elements was5%-15%in the Wuyi Rock Tea. This dissolution rate was in the low level. Even if the finished product Wuyi Rock Tea contained high amount of total rare earth, the human body absorbed very little rare earth elements from the tea. So the Wuyi Rock Tea is very safe and reliable.