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Efficacy of Bitter Blockers on Taste Perception in Children and Adults (BL)

This study has been completed.
National Institute on Deafness and Other Communication Disorders (NIDCD)
Information provided by (Responsible Party):
Julie A. Mennella, Monell Chemical Senses Center Identifier:
First received: July 19, 2011
Last updated: March 14, 2016
Last verified: March 2016
This proposal describes 2 basic research studies that will be conducted sequentially. Study 1 will test the efficacy of both classic and newly developed "generally recognized as a safe" (GRAS) bitter blockers on the perceived bitterness and acceptance of different classes of bitter-tasting compounds by children and compare their responses to adults. Because variations among and between children and adults in terms of sensitivity to different bitter compounds are due in part to genetically determined receptor variation, the investigators will consider genotype when assessing how well bitter blockers perform. In Study 2, the investigators aim to evaluate different methods (forced-choice procedures, hedonic face scales) used for testing children to determine their reliability and reproducibility.


Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Cross-Sectional
Official Title: Efficacy of Bitter Taste Blockers on Flavor Acceptance in Pediatric Populations

Resource links provided by NLM:

Further study details as provided by Julie A. Mennella, Monell Chemical Senses Center:

Primary Outcome Measures:
  • Proportion of subjects who rate bitter solutions with added bitter blockers as less bitter than the bitter solution alone. [ Time Frame: 2 hours ]
    Primary outcome variables are the proportion of subjects by age group (children and adults) judging a variety of GRAS bitter compounds with a bitter blocker as less bitter or more pleasant than the bitter compound alone (the efficacy of the bitter blocker). At least 5 bitter compounds and 5 GRAS bitter blockers will be used. We will determine how these measures are affected by the age and genotype of the subjects.

Secondary Outcome Measures:
  • Biometrics and Genotype [ Time Frame: One year ]
    For both Studies 1 and 2, the secondary outcome variables include age, genotype of various taste receptor genes (e.g., TAS2R38, TAS2R20, TAS2R31), body weight and height.

  • Differences in bitterness ratings obtained via different pediatric taste-assessment methodologies. [ Time Frame: 2 hours ]
    We will determine whether the bitter-blocker pairings assessed as most effective by the children using the forced-comparison procedure (bitter alone vs bitter plus blocker) yield statistically different ratings when children use a 3-point, 5-point, or 7-point scale (with happy and sad faces to denote the degree of liking and disliking) after children, of varying ages, taste each of these solutions.

Biospecimen Retention:   Samples With DNA

Enrollment: 215
Study Start Date: April 2011
Study Completion Date: March 2016
Primary Completion Date: March 2016 (Final data collection date for primary outcome measure)
Children, Adults
3- to 15-year old children and their parent (adults


Ages Eligible for Study:   3 Years and older   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

Total number of subjects to be enrolled into the study: 300 mothers and 300 children (ages 3-10) =600 total subjects.

Mothers will be recruited from the community of greater Philadelphia through newspaper and online ads and initial interviews are conducted over the telephone.


Inclusion Criteria:

  • Healthy, term children of either sex and all races/ethnicities will be eligible for this study.
  • Children must be between 3 and 10 years of age.

Exclusion Criteria:

  • Children who are on any medications that may alter taste sensitivity
  • Mothers who are pregnant
  Contacts and Locations
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Please refer to this study by its identifier: NCT01407939

United States, Pennsylvania
Monell Chemical Senses Center
Philadelphia, Pennsylvania, United States, 19104
Sponsors and Collaborators
Monell Chemical Senses Center
National Institute on Deafness and Other Communication Disorders (NIDCD)
Principal Investigator: Julie A. Mennella, PhD Monell Chemical Senses Center
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Julie A. Mennella, Member, Monell Chemical Senses Center Identifier: NCT01407939     History of Changes
Other Study ID Numbers: 809789
1R01DC011287-01 ( U.S. NIH Grant/Contract )
Study First Received: July 19, 2011
Last Updated: March 14, 2016

Keywords provided by Julie A. Mennella, Monell Chemical Senses Center:
Bitter Taste
Bitter Blockers
Pediatric Medications
Sensory methodology
Children processed this record on September 20, 2017