Mineral content and antioxidant potential of Pu-erh tea of different storage periods

Pu-erh tea is a health-promoting beverage that is consumed in many countries; however, the nutritional value of the tea is significantly affected by various factors including processing and storage. The objective of this study was to investigate the mineral contents and antioxidant potentials of 2-, 9-, and 21-year-old Pu-erh teas. The results demonstrated that the total mineral content of fermented tea (FT) was higher than those of raw tea (RT) after 9 years and 21 years. The 9-year-old FT had the highest K content, while the 2-year-old FT had the lowest K content among the FT samples. In contrast, the 2-year-old RT had the highest K content, while that of the 21-year-old RT was the lowest among the RT samples. Interestingly, the 9-year-old RT had the highest Na, Ca, Mg, and Cu contents among the all of the sampels. Overall, these results reveal that Pu-erh tea stored for 9 years would be the most beneficial with regards to the mineral content and antioxidant potential. Furthermore, this study provides valuable insights into the changes that occur in the nutrient content of Pu-erh tea during storage.