Sensory Analysis and Taste Modulation of Ketone Esters

Ketone Esters for Optimization of Operator Performance in Hypoxia Technical Volume (Sub-project: Sensory Analysis and Taste Modulation of the Ketone Ester)

Ketone ester (KE) drinks are sold commercially in the USA and elsewhere (the FDA has accepted a GRAS (generally regarded as safe) notification on the KEs we propose to study). KE drinks can have beneficial effects on metabolism. Unfortunately, KE drinks have a strongly unpleasant flavor which can trigger rejection. The current study will generate data to help inform KE drink formulations with improved flavor. First stage, trained subjects will rate the intensity of various sensation qualities (e.g., bitter, sour, metallic, and astringent) from KE drinks to help understand the nature of the unpleasant flavor and the particular sensory systems involved (e.g., taste vs. smell). Then, subjects will taste KE drinks with and without various flavor modifiers. Subjects will be healthy adults (aged 21-45) without known food allergies.

Study Overview

• Status: Completed
• Conditions: Flavor Perception in Normal, Healthy Adults
• Intervention / Treatment: Other: Flavor additive

• Study Type: Interventional
• Enrollment (Actual): 19
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19014
      • Monell Chemical Senses Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 45 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Good general health (self report)
2. Men and women
3. Age from 21 to 45

Exclusion Criteria:

1. Current (or within the last four weeks) acute illness, such as cold or flu
2. Currently active allergies
3. Regular use of medication (over the counter or prescription), except for birth control.
4. Any history of food allergy or sensitivity (particularly to KE drinks or MSG). Any history of sensitivity to 6-Propylthiouracil (bitter compound frequently used to assess individual differences in sensitivity to bitterness).
5. Pregnant, nursing, or trying to become pregnant during the study (pregnancy can affect flavor perception)
6. Chronic illness (any ongoing condition that is serious or required medical monitoring), including kidney problems, liver problems, cardiovascular problems (e.g., heart disease or high blood pressure), diabetes, HIV infection, or other ongoing illness). Diabetes or other metabolic issues could be important for safety as well as quality of data.
7. History of taste problems (absent or abnormal sense of taste)
8. Weigh less than 100 pounds (45.4 kilograms). This is to help ensure that the amount of KE drink consumed remains below the single serving in the GRAS (generally regarded as safe) notice which the FDA has accepted.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: OTHER
• Allocation: NA
• Interventional Model: SINGLE_GROUP
• Masking: NONE

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
OTHER: Effect of flavor modifiers; Intervention in the study: Subjects will taste model KE drinks with (control condition) and without (experimental condition) added flavors. Design is within-subjects (subjects will taste both the experimental and control drinks), with order counter-balanced across subjects.	Other: Flavor additive; Various flavor additives will be tested (vs. no added flavor) to determine which show promise for making KE drinks taste less unpleasant

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rated intensity profile	Rated intensity of taste qualities (e.g., sour, bitter) and mouth-feel (astringent) of model drinks, measured using the general Labeled Magnitude Scale (gLMS). In this implementation of the gLMS, scores will range from 0 (or "no sensation") up to 100 ("strongest imaginable sensation"), with higher scores indicating stronger perceived intensity for the sensation in question.	Through study completion (up to a year for a given participant, depending on how many drink samples the participant agrees to evaluate). Participants will rate the intensity of about 12 model drink samples during each study visit.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hedonic response	Ratings of how likely the flavor of each sample tasted would be to discourage use of a product with that flavor, assuming the rater otherwise wanted associated nutritional or performance benefits	Through study completion (up to a year for a given participant, depending on how many drink samples the participant agrees to evaluate). Participants will rate the pleasantness of about 12 model drink samples during each study visit.
Rated upper GI symptoms	Rated intensity of nausea, bloating, and heartburn, using a nine-point category scale (some bitter liquids can trigger mild to moderate feelings of nausea). Scores for each symptom range from 0 ("none") to 8 ("Unbearable"), with "mild" (2), "moderate" (4), and "severe" (6) as labeled intermediate categories.	Through study completion (up to a year for a given participant, depending on how many drink samples the participant agrees to evaluate). Participants will rate upper GI symptoms after tasting about 12 model drink samples during each study visit.

Collaborators and Investigators

• Sponsor: Monell Chemical Senses Center
• Collaborators: HVMN (funding; holder of primary Department of Defense STTR contract)

Study record dates

Study Major Dates

• Study Start (ACTUAL): August 30, 2020
• Primary Completion (ACTUAL): June 4, 2021
• Study Completion (ACTUAL): June 4, 2021

Study Registration Dates

• First Submitted: February 18, 2020
• First Submitted That Met QC Criteria: February 26, 2020
• First Posted (ACTUAL): February 28, 2020

Study Record Updates

• Last Update Posted (ACTUAL): March 21, 2022
• Last Update Submitted That Met QC Criteria: March 4, 2022
• Last Verified: March 1, 2022

More Information

Terms related to this study

• Other Study ID Numbers: SUB055AO1PWise; H92405-19-C-0016 (OTHER_GRANT: SOCOM)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: If individual subject data are shared, the data will be de-identified first (no identifying information will be shared with other researchers).

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No