Abstract:
Objective This study established a method for determining the content of water-soluble silicon in white tea using inductively coupled plasma atomic emission Spectrometry with internal standard method, providing a reliable scientific detection means for studying water-soluble silicon in white tea.
Method White tea samples were ground, dried, extracted with boiling water bath, filtered, and then the filtrate was spiked with internal standard elements, made up to volume, and the content of water-soluble silicon was determined by inductively coupled plasma atomic emission Spectrometry.
Result The standard curve established by this method had a good linearity with a correlation coefficient greater than 0.9999. The detection limit was 7.5 µg·L−1, the relative standard deviation (RSD) was 1.53%, and the recovery rate of sample spiking was between 99.4% and 104.8%. Ten white tea samples collected for detection, including 4 Baimudan and 4 Shoumei each (storage times of 1, 3, 7, and 10 years respectively), and 2 Baimudan (abandoned tea) (storage times of 1 and 3 years respectively), showed that the content of water-soluble silicon in Shoumei tends to increase with the increase of storage years, while the Baimudan of different years remained relatively stable, and the content of water-soluble silicon in Baimudan (abandoned tea) was significantly lower than other categories.
Conclusion This method has good precision and reliable detection results, and is suitable for the determination of water-soluble silicon content in white tea. There is a significant difference in the content of water-soluble silicon among different types of white tea, and in-depth study of water-soluble silicon in white tea is beneficial to provide new ideas for exploring the health effects and quality improvement of white tea.