日本語版

sodium chloride

compound / compound-sodium-chloride

塩化ナトリウム

Sodium chloride. Bitter suppression effect depends on the target compound and concentration.

On this page (7 sections)
  1. Overview
  2. Sources for this overview (3)
  3. Topic hubs
  4. Follow the connections
  5. Related entries (10)
  6. Sensory (3)
  7. Mechanism and receptors (1)
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Reading the bitterness

Sodium salts such as sodium chloride have been reported to suppress bitterness in sensory tests when applied alone and in binary mixtures of multiple bitter compounds. However, suppression was not uniform; in tetralone alone and in mixtures containing tetralone, this suppression effect was not observed (within the scope of the abstract).

In a test where a trained panel of twenty members evaluated bitter perception intensity (average rank score, with 1 = strongest bitterness and 5 = weakest) using the R-Index method with six replicates on a mixed salt solution containing KCl, NaCl, and L-arginine, the results were: 2.02 at a blending ratio of 70:20:10, 2.22 at 65:25:10, 2.86 at 60:30:10, 3.19 at 55:35:10, and 4.72 for the NaCl solution alone as control (p < 0.05 between different groups). Bitter perception intensity decreased significantly as the NaCl blending ratio increased. However, L-arginine was fixed at 10% across all conditions, so only the effect accompanying changes in the KCl ratio could be isolated.

In an experiment using cells engineered to express human bitter taste receptors, the response of cells expressing TAS2R16 to salicin decreased in a concentration-dependent manner in the presence of NaCl in the range of 0–43 mM. In contrast, responses of TAS2R14, TAS2R43, and TAS2R46, which were tested simultaneously, showed no change with NaCl concentration. This is a change in receptor response at the cell level and does not directly measure human sensory bitter perception.

Sources for this overview

  1. The influence of sodium salts on binary mixtures of bitter-tasting compounds

    Keast Russell S J; Canty Thomas M; Breslin Paul A S / 2004 / journal article / abstract checked

    Checked for this overview: Used the compound dependence of the suppression effect, shown by the absence of suppression for tetralone alone.

  2. Saltiness and Bitterness Perception of KCl-Based Mixed Salts (KCl/NaCl/L-Arginine) Evaluated by the R-Index and Partial Projective Mapping Methods

    Chaiya B; Chonpracha P; Waimaleongora-Ek P; Sriwattana S; Prinyawiwatkul W / 2026 / journal article / full text checked

    Checked for this overview: Used the dose-response relationship of R-Index bitter score to NaCl ratio.

  3. Influence of Sodium Chloride on Human Bitter Taste Receptor Responses

    Kumar P; Behrens M / 2024 / journal article / full text checked

    Checked for this overview: Used the NaCl concentration-dependent suppression of TAS2R16 cell response.

Follow the connections

miso →— perceived bitterness is s…→ sodium chloride

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 (3)

sodium chloride can reduce the perceived bitterness of Several bitter substances alone and in binary mixtures (the abstract describes the tested sodium salts, including sodium chloride, together). Tetralone and mixtures containing it, however, were not suppressedpreliminary

Scope: A human sensory test on solutions, with intensities matched to a weak bitterness level. The sodium salts tested were 100 mM sodium chloride, 100 mM sodium gluconate, 100 and 20 mM monosodium glutamate, and 50 mM adenosine monophosphate disodium salt; the result for sodium chloride alone cannot be separated out in the abstract

Note: This claim itself retains a counterexample to any rule that sodium salt uniformly erases bitterness. (2026-10-22, expansion stage N5 stage C batch 6: Codex's check against the source confirmed that the abstract describes the tested sodium salts together, so the result for sodium chloride alone, the subject of this claim, cannot be separated out; lowered from supported to preliminary.)

The sodium salts tested suppressed the bitterness of the compounds and their binary mixtures to differing degrees. Most were suppressed, but tetralone alone and mixtures containing tetralone were not.
Limitations: Abstract only. Panel size and the effect size for each compound are unconfirmed. The abstract describes the tested sodium salts together, so the result for sodium chloride alone cannot be separated out. The solvent of the solutions is also not stated explicitly in the abstract.
Source: The influence of sodium salts on binary mixtures of bitter-tasting compounds (Keast Russell S J; Canty Thomas M; Breslin Paul A S, 2004) · abstract checked
Show datacompound-sodium-chloride —can_reduce_perceived_bitterness_of→ (the claim sentence above)
claim: clm-sodium-suppression-compound-specific / type: sensory / updated: 2026-10-22
sodium chloride can reduce the perceived bitterness of In a KCl:NaCl:L-arginine mixed-salt solution, raising the NaCl proportion from the 70:20:10 and 65:25:10 groups to the 60:30:10 and 55:35:10 groups significantly lowered perceived bitterness intensity (mean rank score) by the R-Index method (the significant difference was shown between the two groups).supported

Scope: Layer: solution. Aqueous solutions of KCl:NaCl:L-Arg mixing ratios 70:20:10/65:25:10/60:30:10/55:35:10 and a control (100% NaCl), at concentrations of 0.5/1.0/1.5% w/v, R-Index method (6 replicates) with a trained panel of 20.

Note: L-arginine (10%) is fixed across all conditions, so what can be isolated is the effect that accompanies changes in the KCl proportion. This does not show the effect of NaCl alone on bitter substances other than KCl.

"Regardless of salt concentration, the KCl-based salt solutions were perceived as less salty and more bitter than the NaCl solution." Mean bitterness rank scores in Table 5 (1 = strongest, 5 = weakest, at 1.0% w/v): A (70:20:10) = 2.02a, B (65:25:10) = 2.22a, C (60:30:10) = 2.86b, D (55:35:10) = 3.19b, E (0:100:0, NaCl control) = 4.72c (different superscript letters indicate a significant difference, p<0.05).
Limitations: L-arginine (10%) is fixed across all conditions, so what is isolated is the effect of increasing or decreasing the KCl proportion. This is a solution system and does not show the effect within a food matrix.
Source: Saltiness and Bitterness Perception of KCl-Based Mixed Salts (KCl/NaCl/L-Arginine) Evaluated by the R-Index and Partial Projective Mapping Methods (Chaiya B; Chonpracha P; Waimaleongora-Ek P; Sriwattana S; Prinyawiwatkul W, 2026) · full text checked
Show datacompound-sodium-chloride —can_reduce_perceived_bitterness_of→ (the claim sentence above)
claim: clm-w72a1-nacl-kcl-mixed-salt-bitterness-reduction / type: sensory / updated: 2026-09-08
miso — perceived bitterness is suppressed by: sodium chloridesupported

Scope: Water-soluble fractions (W-S, extracted with water) and butanol-soluble fractions (Bu-S) of salt-free soybean miso, soybean miso and Hatcho miso, and aqueous solutions of bitter amino acids. The panel ranged from 3 to 32 people depending on the test (8 for paired comparison, 30 for ranking, 32 for pairwise comparison, and 3 for comparison with a bitterness reference substance)

Note: These are tests on an extract of the water-soluble components of miso and on solutions of bitter amino acids, not on miso soup itself. Numerical values for the strength of bitterness are in Tables 1 to 5, but some tables can be read only as images, so the judgments in the text were used. Some tests had small panels (3 and 8 people). The text states that in an earlier report from the same research group, a sensory test of miso soup with salt and nitrogen concentrations adjusted found no difference in bitterness between salt-free soybean miso and ordinary soybean miso, so differences may not appear at the concentration of miso soup. Glutamic acid (100 mg/100 mL) also weakened the bitterness of the bitter amino acids, and worked better than aspartic acid. Desalting lowered not only salt but also pH slightly and nitrogen components, so the desalting comparison alone cannot separate the effect of salt itself (the salt-addition tests do not have this confound).

Point (1) of the Japanese summary states that the 10-fold diluted W-S solution of salt-free soybean miso, the soybean miso W-S solution desalted to 0.02% salt, and bitter amino acid solutions (100 mg/100 mL each) each had a strong bitterness, which was weakened by adding 0.25% or more salt; point (2) states that the strong bitterness of the Bu-S solution (10 mg/mL) of each soybean miso and of the W-S solution of salt-free soybean miso (100 mg/mL) was weakened in 1% salt water. The text states, for the paired comparison (two-point discrimination) of the 10-fold diluted W-S solution of soybean miso and its desalted solution (8 people), that at a risk level of 5% the desalted solution was judged bitter, so desalting strengthens bitterness; for the ranking test with 0 to 1.0% salt added to the W-S solution of salt-free soybean miso (30 people, Friedman), that when 0.25% or more is added, bitterness tends to weaken the more salt is added; and that the bitter amino acids dissolved in distilled water (Table 2, 10 mg/mL each; Phe and Trp ++++, Leu and Val +++) in 1% salt water tasted slightly bitter or were hardly perceived.
Limitations: Extracts of miso and solutions of bitter amino acids, not miso soup itself. Includes tests with panels of 3 and 8 people. Desalting lowered not only salt (to 0.02%) but also pH slightly and nitrogen components, so the desalting comparison alone cannot separate the effect of salt itself. The single bitter amino acids (Table 2) were 10 mg/mL each, while the mixture tests (Tables 4 and 5) were 100 mg/100 mL each, so the concentrations differ. The text states that in an earlier report from the same research group, there was no difference in bitterness between salt-free soybean miso and ordinary soybean miso at the concentration of miso soup.
Source: 豆味噌の苦味に及ぼす食塩の影響 (Effect of Sodium Chloride on Bitterness of Desalted Soybean Miso) (岡田安司; 山口直彦; 好井久雄, 1997) · full text checked
Show dataingredient-miso —has_perceived_bitterness_suppressed_by→ compound-sodium-chloride
claim: clm-soybean-miso-sodium-chloride-bitterness-okada-1997 / type: sensory / updated: 2026-10-21

Mechanism and receptors (1)

sodium chloride can decrease In cells expressing the human bitter receptor TAS2R16, the response to the bitter glycoside salicin was significantly reduced in the presence of NaCl, showing concentration-dependent suppression over the 0-43 mM range. By contrast, the responses of TAS2R14, TAS2R43, and TAS2R46, tested at the same time, showed no change with NaCl concentration.supported

Scope: Layer: cells. TAS2R14, TAS2R16, TAS2R43, and TAS2R46 expressed in HEK293T-Gα16gust44 cells, combinations of each receptor's principal agonist with NaCl concentrations (0/22/43/65/87/108/130 mM), calcium imaging.

Note: Shows at the cellular level that NaCl suppresses receptor response specifically for the target compound (the TAS2R16-salicin pair only), supporting the existing item description 「苦味抑制効果は対象化合物と濃度に依存する」 (in translation: "the bitterness-suppressing effect depends on the target compound and concentration"). A sodium gluconate control confirms this is an effect of the sodium ion rather than the chloride ion.

NaCl affected only the responses of particular bitter taste receptor-compound pairs, and other bitter responses stayed unchanged when sodium concentrations varied. Among the receptors tested, TAS2R16 showed reduced signaling in the presence of NaCl. The maximum response to 30 mM salicin was, on average, 25% larger in the absence of NaCl than with sodium salt. The inhibitory effect of sodium salt on the TAS2R16-salicin response shows a considerable, dose-dependent reduction between 0 mM and 43 mM NaCl.
Limitations: This is a cell-level receptor assay and does not directly measure human sensory bitterness perception. The authors state that whether the inhibition arises from an interaction of NaCl with the bitter compound, the receptor, or solution properties remains undetermined in this study.
Source: Influence of Sodium Chloride on Human Bitter Taste Receptor Responses (Kumar P; Behrens M, 2024) · full text checked
Show datacompound-sodium-chloride —can_decrease→ (the claim sentence above)
claim: clm-w72a1-nacl-tas2r16-salicin-inhibition / type: mechanism / updated: 2026-09-08

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