Regularity of characteristic components of large-leaf tea (Camellia sinensis) flowers at different reproductive stages

This study examined the dynamic changes in the characteristic components of tea flowers throughout their reproductive stages. The taste and aroma components were analyzed across seven reproductive stages of the YunKang-10 (YK10), XueYa-100 (XY100), and PuJing-1 (PJ1) tea flowers. The results revealed that the concentrations of tea polyphenols, total flavonoids, and caffeine were highest during the initial stage and decreased over time. During the early blooming period, the tea flowers exhibited a lower phenol-ammonia ratio and higher soluble sugar content. Additionally, soluble sugar, gallocatechin, epicatechin gallate, water extracts, epigallocatechin gallate, and total flavonoids were identified as key indicators for differentiating between various large-leaf tea flower varieties. Among the volatiles from stage 1 to stage 7, linalool, with its floral and citrus aroma, was the most abundant. Dihydroactinolide, associated with the fruity aroma of tea flowers, was more prominent in the pre-reproductive stage. Ethyl palmitate and acetophenone, both contributing to the floral aroma, began to increase in concentration from stage 4. Additionally, 1-phenylethanol, known for its sweet aroma, reached higher levels at stage 5. These findings offer a crucial theoretical foundation for the further development of tea flower products. • Revealing the regulation of biochemical processes of tea flowers in stages. • Soluble sugar and six other substances can distinguish different tea flowers. • 54 volatile substances were found to be enriched in tea flowers. • 1-PE and linalool, abundant in S5, contribute to the sweet and fruity aroma.