pine smoke withering
process / process-pine-smoke-withering
松の煙による萎凋
Pine smoke withering is a distinctive step in the withering of (Lapsang Souchong) in which tea leaves are exposed to pinewood smoke.
On this page (8 sections)
Reading the bitterness
「正山小種」 (Lapsang Souchong) is a black tea made by a distinctive process: during withering and drying, tea leaves in bamboo baskets are hung over a pinewood fire to absorb its smoke. This is described as a traditional method originating in the Tongmu area of Wuyi Mountain, Fujian Province.
Exposure to pine smoke has been found to change the tea's bitterness itself, beyond adding aroma. A study combining electronic-tongue measurement, sensory evaluation, and cell-based calcium imaging reported that pine-smoke withering significantly reduced the bitterness of 「正山小種」 (Lapsang Souchong).
As a possible basis for lower bitterness, untargeted metabolomics was reported to find large decreases in major bitter phenolics after pine-smoke withering, including 10 monomeric catechins, 14 glycosylated flavonols, and 6 galloylated phenolic acids. This report has been checked only at abstract level; details such as panel size and electronic-tongue output values require reading the full text.
Pine-smoke withering also substantially reshapes aroma compounds. GC and GC-MS analysis reported decreases in tea-derived aroma compounds but marked increases in pine-derived terpenes and pyrolysis products including guaiacol, 4-methylguaiacol, and 4-ethylguaiacol; these were not detected in unsmoked 「正山小種」 (Lapsang Souchong). Lower bitterness and substantial aroma change arise from the same step.
The abstract shows that guaiacol and alpha-terpineol, aroma compounds from pine-smoke withering, suppressed TAS2R14 activation by a pre-withering tea extract by 37% and 21%, respectively, measured as changes in intracellular calcium signaling. Quantum chemical calculations indicate that these aroma compounds interact with bitter molecules mainly through intermolecular hydrogen bonds and van der Waals forces.
Sources for this overview
Checked for this overview: Confirmed the specific steps of withering under pine smoke. / Confirmed the pattern of changes in pine-derived aroma compounds.
Role of smoke withering process in the bitterness amelioration effect on smoked Lapsang Souchong tea
Checked for this overview: Confirmed significant bitterness reduction through multiple methods. / Confirmed the breakdown of decreased bitter phenolics. / A receptor-level mechanism involving direct suppression of TAS2R14 activation by aroma compounds.
Follow the connections
Lapsang souchong →is processed by→ pine smoke withering
bitterness →is reduced by→ pine smoke withering
pine smoke withering →reduces→ TAS2R14
Structured claims — open a section to read each claim's confidence, evidence and limits
Sensory (1)
Scope: A comparison before and after the pine-smoke withering process for lapsang souchong (smoked tea)
Note: Using a method integrating electronic-tongue analysis, sensory evaluation, and a cell-based calcium-imaging assay, the pine-smoke withering process was confirmed to significantly reduce the tea's bitterness. The study reports that non-targeted metabolomics found pine-smoke withering to have greatly decreased the major bitter phenolics, including 10 monomeric catechins, 14 glycosylated flavonols, and 6 galloylated phenolic acids. The full text has not been confirmed; this is abstract-level information.
Show data
sensation-bitter —is_reduced_by→ process-pine-smoke-witheringMechanism and receptors (1)
Scope: Layer: cell. Effects on TAS2R14 were measured with a cell-based calcium-imaging assay.
Note: Full text not checked; confirmed from the full abstract as posted on Semantic Scholar. Separately from the 2 existing claims (confirmation of reduced bitterness, and the decrease in bitter phenolics), this adds a mechanism by which the aroma compounds themselves directly suppress the bitterness signal at the receptor level.
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process-pine-smoke-withering —reduces→ receptor-tas2r14How processing and cooking change it (1)
Scope: 「正山小種」 (Lapsang Souchong), a traditional production method originating in the Tongmu area of the Wuyi Mountains, Fujian Province.
Note: In the pine-wood smoking step, aroma constituents from the tea decrease while pine terpenoids (such as longifolene) and pyrolysis products (such as guaiacol, 4-methylguaiacol and 4-ethylguaiacol) increase markedly. These were identified only in this kind of black tea. The abstract gives no figures for smoking temperature or time. External audit N2-2 (2026-10-20): the basis was replaced from a search-engine summary with the official PubMed abstract (PMID 16248572), and the process detail not in the abstract (hanging the leaves in bamboo baskets over the fire) was removed.
Show data
ingredient-lapsang-souchong —is_processed_by→ process-pine-smoke-withering