astringency
sensation / sensation-astringent
渋味
Astringency is an oral mouthfeel often described through subqualities such as dryness, roughness, and puckering.
On this page (11 sections)
Reading the bitterness
「渋味」 (in translation: "astringency") is described as a sensation distinct from bitterness: an oral feeling with several qualities, including dryness, roughness, and puckering. Multiple reviews distinguish it from bitterness, which is mediated by taste buds. The two can occur together and perception of one can affect perception of the other, making them easy to confuse when eating or drinking. Nevertheless, these reviews treat astringency as a distinct sensation, not as identical to bitterness.
Proposed mechanisms of astringency include reduced salivary lubrication, increased friction in the mouth, and responses from receptors beyond touch. It remains unresolved how much each mechanism contributes, and a single chemical or physical measure is described as insufficient to predict astringency intensity. For tannins, common sources of astringency, proposed mechanisms include binding to salivary proteins or oral mucosa and neural involvement. Higher-polymerization tannins also tend to produce stronger astringency, whereas smaller molecules tend toward stronger bitterness.
In brewed green tea, astringency is treated as a major feature separate from bitterness. One quantitative study found that its intensity correlated with concentrations of the catechin ECG and glycosides of myricetin and quercetin. A separate study of black tea, however, used taste-dilution methods to seek the principal causes of astringency and identified 14 flavonol glycosides rather than catechins, so the studies do not agree. A finding that longer extraction increases astringency has been confirmed only within the scope of a model experiment using oolong tea.
A study attempting to explain individual differences in astringency through recovery of salivary proteins after stimulation accounted for 33% and 29% of the differences for astringent substances dissolved in water, but those same measures could not predict astringency in solid test foods. A molecular-level study found that caffeine partly occupied binding sites on salivary proteins and thus weakened the astringency of the tea catechin EGCG, but it did not directly measure people’s actual perception. Astringency also has an entry in an international sensory-evaluation vocabulary standard, although the definition text has not been checked.
Sources for this overview
Checked for this overview: Confirmed the classification of astringency as an oral tactile sensation distinct from bitterness. / Confirmed proposed mechanisms involving reduced lubrication, friction, and receptor responses. / Confirmed the limit that a single measurement does not predict astringency.
Tannins in Food: Insights into the Molecular Perception of Astringency and Bitter Taste
Checked for this overview: Confirmed that the two sensations can occur together and are easily confused. / Confirmed proposed tannin-binding mechanisms and the trend with degree of polymerization.
Checked for this overview: Confirmed that astringency is treated as a major green-tea quality attribute separate from bitterness.
Quantitative analyses of the bitterness and astringency of catechins from green tea
Checked for this overview: Confirmed the correlation of green-tea ECG with astringency at R2=0.79.
Checked for this overview: Confirmed the conflicting black-tea result identifying flavonol glycosides as the main contributors.
Checked for this overview: Confirmed the association between extraction time and increased astringency in the oolong-tea model.
Salivary protein levels as a predictor of perceived astringency in model systems and solid foods
Checked for this overview: Confirmed that salivary-protein recovery accounted for 30% of individual differences. / Confirmed that the same indicator failed to predict astringency in solid foods.
Checked for this overview: Confirmed a molecular mechanism by which caffeine weakens EGCG astringency.
Sensory analysis — Vocabulary (ISO 5492:2008, incl. Amd 1:2016)
Checked for this overview: Confirmed that an ISO international standard has a vocabulary entry for astringency.
Other names: astringence (fr)
Follow the connections
astringency →is not synonymous with→ bitterness →is reduced by→ sweetness
tannins →can elicit→ astringency
green tea infusion →— sensory attribute→ astringency
astringency →reduces taste preference for→ chokeberry →— sensory attribute→ bitterness
Hypotheses and recipe candidates for this entry are on the Japanese page.
Structured claims — open a section to read each claim's confidence, evidence and limits
Sensory (18)
Scope: How it is felt when eating or drinking food or beverages
Note: The two can occur together and each can affect how the other is felt, but bitterness as a taste and astringency as a dryness/roughness are recorded separately. / 2026-08-31: Calibration downgrade from established to supported, because the supporting evidence does not derive from a full-text check. Can be re-upgraded after a full-text check.
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sensation-astringent —is_not_synonymous_with→ sensation-bitterScope: Instrumental prediction of human astringency
Note: A measurement generally captures only the mechanism it models.
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sensation-astringent —is_not_fully_predicted_by→ "A single chemical or physical measurement"Scope: Food tannins
Note: Intensity and quality depend on structure, concentration, and matrix.
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compound-tannins —can_elicit→ sensation-astringentScope: Brewed green tea
Note: Kept separate from bitterness even where the compounds driving the two overlap. / 2026-08-31: Calibrated down from established to supported, because the supporting evidence does not derive from a full-text check. May be re-upgraded after a full-text check.
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ingredient-green-tea —has_sensory_attribute→ sensation-astringentScope: Green tea infusion in the cited quantitative study.
Note: Subject to interactions within the mixture and preparation conditions.
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compound-ecg —is_correlated_with→ sensation-astringentScope: Selected myricetin and quercetin glycosides in the green tea research cited
Note: A single fixed astringent character should not be assigned to this broad class.
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compound-flavonol-glycosides —are_correlated_with→ sensation-astringentScope: International standard terminology concerning sensory attributes.
Note: The text of the definitions has not been reproduced. Full-text access is paid.
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sensation-astringent —has_standardized_vocabulary_entry_in→ "ISO 5492 sensory analysis vocabulary."Scope: Tea infusions. Asserted for green tea; contradicted for black tea.
Note: The green tea literature regards catechins as the main contributor to astringency, but a taste-dilution study on black tea found flavonol glycosides to be dominant instead. The matrix (green tea vs. black tea) and the method (correlation vs. dilution-to-threshold) differ.
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compound-catechins —are_main_contributors_to→ sensation-astringentScope: A study that evaluated samples of tannic acid or alum dissolved in water
Note: The individual differences explained by the degree to which salivary protein returned after stimulation were 33% and 29% — not a figure that explains all of how astringency is perceived.
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sensation-astringent —is_partially_predicted_by→ concept-salivary-protein-replenishmentScope: Group A saponin fraction isolated from unprocessed soybean (sensory evaluation)
Note: Okubo (1988) gives the taste of saponin A in the legend of Figure 1 as 「強い苦味、弱い収斂味」 (in translation: "strong bitterness, weak astringency"). In Table 1 of the same report, group A saponins (from hypocotyls) are described as 「嫌悪感、苦味、収斂味、ざらつき」 (in translation: "aversive, bitter, astringent, gritty"), with no degree word on astringency. Bitterness and astringency are recorded as separate claims. The contribution to astringency is weak.
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compound-class-soyasaponin-group-a —contributes_to→ sensation-astringentScope: Isoflavone glycosides isolated from raw, unprocessed soybean (sensory test)
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compound-class-soy-isoflavone-glycosides —contributes_to→ sensation-astringentScope: Laboratory conditions in which milk was added to an aqueous EGCG (gallated catechin) solution, using an oral-tribology system modeled on the salivary film.
Note: In the same experiment, milk instead substantially reduced the lubricity of the salivary lubricating film; relief of perceived astringency therefore cannot be explained by a decrease in the coefficient of friction alone. This was a result in an aqueous EGCG model system, not an experiment using a green-tea infusion or an actual matcha latte. The existing process-milk-addition entry describes adding cow’s milk or oat beverage to coffee; this claim has separate scope_text because it concerns tea catechins in a different context.
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process-milk-addition —can_decrease→ sensation-astringentScope: Generic descriptive analysis of blackcurrant juices and press-residue fractions prepared by various processing and fractionation methods.
Note: Regardless of processing, sourness and puckering astringency are reported as the strongest sensory attributes in the juice. Sugars and acids are mainly in juice fractions and phenolic compounds mainly in press-residue fractions.
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ingredient-blackcurrant —has_sensory_attribute→ sensation-astringentScope: The same evaluation, rating 6 attributes: sweetness, bitterness, sourness, astringency, thickness, and cranberry flavor.
Note: Within the same descriptive evaluation as bitterness, astringency was measured and reported simultaneously as an independent attribute.
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ingredient-cranberry —has_sensory_attribute→ sensation-astringentScope: The same panel as above.
Note: Astringency was rated as an independent attribute in the same descriptive panel as bitterness.
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ingredient-aronia —has_sensory_attribute→ sensation-astringentScope: Correlation analysis of ratings of overall liking in the same study.
Note: The study reports that liking correlated strongly and primarily with perceived sweetness intensity (ρ=0.96), while astringency correlated negatively with liking. The correlation between bitterness and liking cannot be confirmed from this abstract, so this claim records only the astringency correlation.
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sensation-astringent —reduces_taste_preference_for→ ingredient-aroniaScope: Same as above.
Note: Astringency is also listed in the same description as bitterness and sourness.
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ingredient-lingonberry —has_sensory_attribute→ sensation-astringentScope: Linne et al. 2025; 9 trained panelists (6 women, 3 men, aged 23–47); same/different judgments with confidence ratings; 27 evaluations per sample; nose clips worn.
Note: F9.6.4 is a brown, condensed-phenolic-dominated complex fraction obtained by multistep fractionation of the fraction below 5 kDa; the authors describe it as melanoidins or their precursors. It is not a purified single substance. The free descriptions were drying/astringent, not a measurement of bitterness.
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compound-class-melanoidins —has_sensory_attribute→ sensation-astringentMechanism and receptors (2)
Scope: Current review literature
Note: The relative role of each mechanism, and of the proposed subqualities, remains unresolved.
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sensation-astringent —has_currently_proposed_mechanisms→ "Loss of salivary lubrication, increased oral friction, and non-tactile receptor responses are among the mechanisms proposed."Scope: In an EGCG/caffeine/saliva model, the astringency of EGCG when caffeine partially occupied EGCG binding sites on salivary proteins
Note: Assessed by molecular docking, ITC, and salivary rheology. Perceived astringency was inferred from salivary film structure; the abstract reports no human panel data.
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compound-caffeine —can_decrease→ sensation-astringentHow processing and cooking change it (1)
Scope: Tea infusions in an artificial oil-body study.
Note: Human sensory confirmation and details of the extraction conditions are needed.
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process-brewing-time —can_increase→ sensation-astringentSafety and regulation (2)
Scope: OIV's ‘Sensory Analysis of Wine’ document (March 2016), Part I b), the section on tests for judging sensory acuity. Covers the sensory panel training program for grapes and grape-derived beverages (moûts, vins et autres boissons d'origine vitivinicole).
Note: The same section lists the five basic tastes to be checked in stimulus-detection training as ‘sweet, sour, salty, umami, bitter,’ with astringency (astringence) appended alongside it in a separate category, as "ainsi que" (in addition). The document’s own opening Avertissement states that it has not gone through the member-state resolution review procedure and "cannot be treated as an OIV resolution," being a subcommittee consensus document instead — so this claim is recorded as a record of institutional positioning, not a claim of established scientific consensus.
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sensation-bitter —can_be_measured_separately_from→ sensation-astringentScope: The same document, Part I, Table 1. Placed as a separate entry for astringency within the same table as the bitterness reference (quinine sulfate).
Note: A record that, within the same training table, the reference substance for bitterness (quinine sulfate) and the reference substance for astringency (tannic acid) are clearly separated as distinct rows.
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compound-tannins —is_used_as_sensory_reference_for→ sensation-astringentCulture (2)
Note: Kotobank (Revised Edition of the Nihon Kokugo Daijiten). A record of the fact that the Japanese taste word 「渋い」 (in translation: “shibui”) is itself defined with the astringent persimmon as its reference point.
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sensation-astringent —has_name_etymology→ "The Japanese word 「渋い」 (in translation: “shibui, astringent”) is traced to the Muromachi-period adjective 「渋し」 (in translation: “shibushi”). The Revised Edition of the Nihon Kokugo Daijiten defines one of its senses as 「渋柿をかじったような、舌をしびれさせるような味である」 (in translation: “a taste like that of biting into an astringent persimmon, that numbs the tongue”), and cites, as its earliest recorded usage, a line from a Muromachi-period kyogen play: 「さればこそしぶいが一定じゃ、そうじてしぶがきをくふては、うそがふかれぬ」 (in translation: “That's exactly why it is shibui — indeed, eating an astringent persimmon puckers the mouth so that one cannot whistle.”)"Show data
sensation-astringent —is_presented_as→ "In the thesaurus entry for 「渋い」 (in translation: “astringent”) in the Digital Daijisen, 「苦い」 (in translation: “bitter”) and 「ほろ苦い」 (in translation: “mildly bitter”) are listed as synonyms."