Chemosensory Perception

, Volume 6, Issue 1, pp 8–19 | Cite as

Masking Vegetable Bitterness to Improve Palatability Depends on Vegetable Type and Taste Phenotype

  • Mastaneh Sharafi
  • John E. Hayes
  • Valerie B. DuffyEmail author


Consumption of dark green vegetables falls short of recommendations, in part, because of unpleasant bitterness. A laboratory-based study of 37 adults was used to determine bitter and hedonic responses to vegetables (asparagus, Brussels sprouts, kale) with bitter masking agents (1.33 M sodium acetate, 10 and 32 mM sodium chloride, and 3.2 mM aspartame) and then characterized by taste phenotype and vegetable liking. In repeated-measures ANOVA, aspartame was most effective at suppressing bitterness and improving hedonic responses for all sampled vegetables. Among the sodium salts, 32 mM sodium chloride decreased bitterness for kale and sodium acetate reduced bitterness across all vegetables with a tendency to increase liking for Brussels sprouts, as release from mixture suppression increased perceived sweetness. Participants were nearly equally divided into three 6-n-propylthiouracil (PROP) phenotype groups. Those tasting the least PROP bitterness (non-tasters) reported least vegetable bitterness, and the additives produced little change in vegetable liking. Aspartame persisted as the most effective bitter blocker for the PROP tasters (medium, supertasters), improving vegetable liking for the medium tasters but too much sweetness for supertasters. The sodium salts showed some bitter blocking for PROP tasters, particularly sodium acetate, without significant gains in vegetable liking. Via a survey, adults characterized as low vegetable likers reported greater increase in vegetable liking with the maskers than did vegetable likers. These results suggest that bitter masking agents (mainly sweeteners) can suppress bitterness to increase acceptance if they are matched to perceived vegetable bitterness or to self-reported vegetable disliking.


Bitter Food preference Genetics Salt Sweet Taste Vegetables 



The project received supported from the American Diabetes Association Foundation and USDA Hatch Project CONS00827. JEH receives salary support from USDA Hatch Project PEN04332 funds and a National Institutes of Health grant from the National Institute of Deafness and Communication Disorders (grant DC010904).


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Mastaneh Sharafi
    • 1
  • John E. Hayes
    • 2
  • Valerie B. Duffy
    • 1
    Email author
  1. 1.Department of Allied Health Sciences, College of Agriculture and Natural ResourcesUniversity of ConnecticutStorrsUSA
  2. 2.Department of Food Science, College of Agricultural SciencesThe Pennsylvania State UniversityUniversity ParkUSA

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