Phenolic compounds, antioxidant activity and sensory evaluation of sea buckthorn (Hippophae rhamnoides L.) leaf tea

Sea buckthorn leaf tea, an emerging potential functional beverage product, has not yet had appropriate product standards and corresponding quality evaluation methods, and its poor taste directly affects the acceptance of the population, thus limiting its market consumption potential. In this study, two major packaging forms of sea buckthorn leaf tea available in the Chinese market were selected. The contents of total phenolics, total flavonoids, and 10 phenolic compounds, as well as the in vitro antioxidant capacity and sensory characteristics of sea buckthorn leaf tea were analyzed. Results showed that the quality of sea buckthorn leaf tea in the Chinese market varied widely. The total phenolic content, total flavonoid content, antioxidant activity, and consumer acceptance of bagged sea buckthorn leaf tea were higher than those of bulk sea buckthorn leaf tea. Multifactorial statistical analysis showed that the taste astringency of sea buckthorn leaf tea was closely related to ellagic acid and isorhamnetin-3-O-neohesperidin. Furthermore, isorhamnetin-3-O-neohesperidin had a greater effect on the antioxidant activity of sea buckthorn leaf tea. Therefore, ellagic acid and isorhamnetin-3-O-neohesperidin can be used as potential quality markers for sea buckthorn leaf tea. This work provides a reference for taste improvement and quality control of sea buckthorn leaf tea.