Chemosensory Perception

, Volume 7, Issue 1, pp 10–22 | Cite as

Sodium Chloride Suppresses Vegetable Bitterness Only When Plain Vegetables Are Perceived as Highly Bitter

  • Lynn M. WilkieEmail author
  • Elizabeth D. Capaldi Phillips
  • Devina Wadhera


The efficacy of sodium salts as bitterness suppressors is highly variable depending on the tastants used, and few studies have investigated whether salt can mask the bitterness of nutritious vegetables. We compared how sodium chloride (NaCl) affected bitterness ratings of vegetables and quinine hydrochloride (QHCl). In Experiment 1, Brussels sprouts and cauliflower were rated plain and with the addition of NaCl on hedonic and sensory attributes. In Experiment 2, multiple concentrations of NaCl were given on the vegetables, and participants tasted QHCl plain and with the addition of NaCl. In both experiments, reported bitterness and liking of the vegetables did not change with the addition of NaCl; all p values > 0.3. Hierarchical linear regression modeling revealed that NaCl decreased the bitterness ratings of the vegetables most for participants who perceived the plain vegetables as highly bitter, R 2 = 0.211, and increased hedonic ratings of the vegetables most for participants who disliked the plain vegetables, R 2 = 0.243. The addition of NaCl to QHCl significantly reduced bitterness ratings, p < 0.001, especially for participants who found the plain QHCl highly bitter, R 2 = 0.339. Sodium chloride suppressed bitterness and increased liking for participants who disliked plain vegetables and tasted them as highly bitter. These results suggest that NaCl would be efficacious as a bitterness masking agent for people particularly vulnerable to vegetable underconsumption. Furthermore, NaCl might interact fundamentally differently with a full food matrix than it does with QHCl, limiting the generalizeability of chemical suppression studies.


Bitterness suppression Salt Sodium chloride Individual differences Quinine hydrochloride 



Analysis of variance


Adenosine triphosphate


Body mass index


Generalized labeled magnitude scale


Potassium chloride




Magnesium sulfate


Sodium acetate


sodium chloride






Quinine hydrochloride


Recommended daily allowance


Compliance with Ethics Requirements

Conflict of Interest

Lynn M. Wilkie declares that she has no conflict of interest.

Elizabeth D. Capaldi Phillips declares that she has no conflict of interest.

Devina Wadhera declares that she has no conflict of interest.

All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008 (5). Informed consent was obtained from all patients for being included in the study.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Lynn M. Wilkie
    • 1
    Email author
  • Elizabeth D. Capaldi Phillips
    • 1
  • Devina Wadhera
    • 1
  1. 1.Arizona State UniversityTempeUSA

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