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flavonol glycosides

compound class / compound-flavonol-glycosides

フラボノール配糖体

glycosylated flavonol compounds found in tea, cacao, and other plants.

On this page (6 sections)
  1. Overview
  2. Sources for this overview (3)
  3. Topic hubs
  4. Follow the connections
  5. Related entries (10)
  6. Sensory (4)
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Reading the bitterness

Flavonol glycosides are glycosylated flavonoids found in multiple plants including tea and cacao. In research modeling green tea infusion, the concentrations of selected myricetin and quercetin glycosides were shown to correlate with astringency.

In taste dilution analysis of black tea infusion, a series of 14 flavone-3-ol glycosides—not theaflavins or catechins—was identified as the principal contributors to astringency. At an extremely low threshold of 0.001 μmol/L, quercetin-3-O-rutinoside has been reported to evoke a velvety oral coating sensation. In an abbreviation experiment narrowing a taste model of black tea composed of 51 compounds to 12 key compounds, 9 flavonol-3-glycosides carrying velvety astringency remained in the reduced model.

The same black tea reconstitution experiment also showed for the first time that flavanol-3-glycosides amplify not only astringency but also the bitterness of caffeine. This is an example of interaction between compounds, wherein an astringency-bearing component strengthens the bitterness of another compound. The magnitude of the amplification itself is not shown in the abstract.

All of these findings remain at the abstract level of confirmation and have not reached individual threshold tables or detailed numerical values from the abbreviation trials. Care should be taken not to assign a single fixed astringent character uniformly to the broad class of flavonol glycosides as a whole.

Sources for this overview

  1. Quantitative analyses of the bitterness and astringency of catechins from green tea

    Xu YQ; Zhang YN; Chen JX; Wang F; Du QZ; Yin JF / 2018 / journal article / abstract checked

    Checked for this overview: Confirmation of glycoside concentration and astringency correlation in green tea / Confirmation of the limitation of avoiding uniform characterization across the broad class

  2. Identification of the astringent taste compounds in black tea infusions by combining instrumental analysis and human bioresponse

    Scharbert S; Holzmann N; Hofmann T / 2004 / journal article / abstract checked

    Checked for this overview: Confirmation of 14-type glycoside and low-threshold astringency contribution in black tea

  3. Molecular definition of black tea taste by means of quantitative studies, taste reconstitution, and omission experiments

    Scharbert S; Hofmann T / 2005 / journal article / abstract checked

    Checked for this overview: Confirmation that 9 types of glycosides remain in the abbreviated model in the omission experiment / Confirmation of the first report that glycosides amplify caffeine bitterness

Follow the connections

flavonol glycosides →are correlated with→ astringency →is not synonymous with→ bitterness

flavonol glycosides →amplifies the bitterness of→ caffeine →is a poor universal prototy…→ bitterness

blackcurrant →— astringency correlates wi…→ flavonol glycosides

Structured claims — open a section to read each claim's confidence, evidence and limits

Sensory (4)

flavonol glycosidesastringency are correlated with supported

Scope: 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.

In modeled green tea infusion, selected flavonol glycosides correlated with astringency.
Limitations: This does not establish that all flavonol glycosides exhibit the same behavior.
Source: Quantitative analyses of the bitterness and astringency of catechins from green tea (Xu YQ; Zhang YN; Chen JX; Wang F; Du QZ; Yin JF, 2018) · abstract checked
Show datacompound-flavonol-glycosides —are_correlated_with→ sensation-astringent
claim: clm-flavonol-glycosides-astringent / type: sensory / updated: 2026-08-30
flavonol glycosidesBlack tea infusion (14 flavone-3-ol glycosides; velvety oral coating sensation at an extremely low threshold) are key astringent compounds of supported

Scope: Freshly brewed black tea infusion. Taste dilution analysis and human sensory verification

Note: The threshold of flavone-3-ol glycosides has been reported to be far lower than that of catechins or theaflavins.

Taste dilution analysis of fresh black tea infusion identified a series of 14 flavone-3-ol glycosides—not theaaflavin-like polyphenols, catechins, or theaflavins—as the principal contributors to astringency. These evoke a velvety oral coating sensation at very low thresholds (quercetin-3-O-rutinoside 0.001 μmol/L).
Limitations: Abstract level. Individual threshold tables have not been accessed.
Source: Identification of the astringent taste compounds in black tea infusions by combining instrumental analysis and human bioresponse (Scharbert S; Holzmann N; Hofmann T, 2004) · abstract checked
An omission experiment reduced a taste model of black tea composed of 51 compounds to 12 key compounds. This included 9 flavonol-3-glycosides with velvety astringency, catechins with puckering astringency, EGCG with astringency and bitterness, and caffeine with bitterness, and the reduced reconstituted liquid did not differ significantly from the complete model.
Limitations: Abstract level; individual compound DoT (dose-over-threshold) factors have not been accessed.
Source: Molecular definition of black tea taste by means of quantitative studies, taste reconstitution, and omission experiments (Scharbert S; Hofmann T, 2005) · abstract checked
Show datacompound-flavonol-glycosides —are_key_astringents_of→ "Black tea infusion (14 flavone-3-ol glycosides; velvety oral coating sensation at an extremely low threshold)"
claim: clm-black-tea-flavonol-glycosides-astringent / type: sensory / updated: 2026-08-30
flavonol glycosidescaffeine amplifies the bitterness of supported

Scope: Reconstituted black tea infusion system. First empirical demonstration reported

Note: The direction is amplification of caffeine bitterness by flavonol-3-glycosides. This differs in both compound pair and attribute from the finding that caffeine weakens EGCG astringency.

Additional sensory research showed that flavonol-3-glycosides not only impart a velvety astringent sensation but also amplify caffeine bitterness, thereby contributing to the bitterness of tea infusions for the first time.
Limitations: The magnitude of amplification is not shown in the abstract.
Source: Molecular definition of black tea taste by means of quantitative studies, taste reconstitution, and omission experiments (Scharbert S; Hofmann T, 2005) · abstract checked
Show datacompound-flavonol-glycosides —amplify_bitterness_of→ compound-caffeine
claim: clm-flavonol-glycosides-amplify-caffeine-bitterness / type: sensory / updated: 2026-08-30
blackcurrant — astringency correlates with: flavonol glycosidespreliminary

Scope: Sensory and chemical analysis of black currant fractionated into juice, ethanol extract, and fiber/seed residue.

Note: Blackcurrant extracts (ethanol-extracted and supercritical-fluid-extracted fractions) were perceived as the most astringent, and 3 flavonol glycosides were named as compounds especially contributing to astringency (abstract). Attribution of bitterness to tannins does not appear in the abstract, and the full text (subscription) has not been checked, so it is withheld. On 2026-10-06 the claim was changed from an attribution of bitterness to tannins, which the abstract does not contain, to the relation between astringency and flavonol glycosides that the abstract describes.

The fraction of extract (ethanol extraction, supercritical fluid extraction) containing abundant phenolic compounds was perceived as the most astringent. Three flavonol glycosides were identified as major compounds contributing to astringency: kaempferol-3-O-(6''-malonyl) glucoside, myricetin-3-O-galactoside, and an unidentified kaempferol glycoside. The abstract contains no mention of bitterness (bitter).
Limitations: The description of bitterness does not exist in the official abstract and cannot be confirmed. Since the full text is unconfirmed due to a paywall, it cannot be determined this time whether the main text contains any description of bitterness.
Source: Orosensory Profiles and Chemical Composition of Black Currant (Ribes nigrum) Juice and Fractions of Press Residue (Mari Sandell; Oskar Laaksonen; Riikka Järvinen; Nina Rostiala; Terhi Pohjanheimo; Katja Tiitinen; Heikki Kallio, 2009) · abstract checked
Show dataingredient-blackcurrant —has_astringency_correlated_with→ compound-flavonol-glycosides
claim: clm-blackcurrant-skin-fraction-bitter / type: sensory / updated: 2026-10-06

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