Abstract
China's ancient tea gardens boast a rich resource, and their unique environmental conditions cause their quality differences. In this study, flavor components and aroma compounds of fresh leaves from four Dancong ancient tea gardens (Zimao (ZMF), Baixiang (BX), Xialiao (HSK), and Da'an (DAF)) at different altitudes were determined by HPLC and GC-MS and then correlated with elemental contents. The results showed that low-altitude tea gardens ZMF had a higher caffeine content (5.21%) and astringency index (0.82) compared to other high-altitude tea gardens, which led to a more bitter taste and astringent sensation. Fresh leaves from ZMF had a higher content of linalool (151.31 μg/kg) and geraniol (61.09 μg/kg) than those of other tea gardens. Correlation analysis showed that the bitter and astringent indexes had a strong correlation with element N content (correlation coefficient: 0.74, 0.48); volatile compounds had significant positive or negative correlations with various elemental contents, among which the correlation coefficient between element Al content and linalool content of fresh leaves was -0.83 (p < 0.001). The fresh leaves of ZMF tea gardens had a higher N content and lower Al, Si, and Hf content, which may cause more bitterness astringency and differences in volatile compounds in their teas than those of higher altitude tea gardens. The results of the study further provide guidance for the scientific management of Dancong ancient tea gardens.