Tea head as a novel by-product of Pu-erh tea: storage-induced flavor reshaping compared with loose tea

Storage plays an important role in the quality development of ripened Pu-erh tea. However, the differential flavor evolution during storage between loose ripened Pu-erh tea (PE) and its by-product, tea head (CT), derived from the same fermentation pile, remains unclear.

In this study, PE and CT were analyzed after storage. Sensory evaluation showed that CT developed stronger umami and sweetness and less bitterness than PE. This was attributed to higher total amino acid (CT2: 8.28 ± 0.44 > PE2: 7.17 ± 0.38 mg g^-1) and soluble sugar content (CT2: 28.10 ± 1.08 > PE2: 21.70 ± 0.95 mg g^-1) and lower catechin (CT2: 28.68 ± 0.30 < PE2: 35.37 ± 0.51 mg g^-1) and caffeine (CT2: 28.76 ± 0.47 < PE2: 30.73 ± 0.33 mg g^-1) content. Tea head exhibited enhanced woody and herbal aromas, likely driven by increased α-ionone, safranal, 6-methylsalicylaldehyde, 1,2,4-trimethoxybenzene, and 1,2-dimethoxybenzene. Pu-erh tea displayed intensified stale and fatty aromas, which were correlated with higher ethyl 5-methyl-vinyl tetrahydrofuran carbonate, 1,2,3-trimethoxybenzene, 1,2,4-trimethoxybenzene, 1,2-dimethoxybenzene, β-ionone, and nonanal content.

Storage can promote changes in CT and PE taste and aroma but with different effects on each. © 2026 Society of Chemical Industry.