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Trial registered on ANZCTR


Registration number
ACTRN12616001356459
Ethics application status
Approved
Date submitted
2/07/2015
Date registered
29/09/2016
Date last updated
29/09/2016
Type of registration
Retrospectively registered

Titles & IDs
Public title
Determination of human oral carbohydrate taste function and its association with food consumption and Body Mass Index (BMI)
Scientific title
Carbohydrate taste sensitivity testing in healthy volunteers to determine human oral carbohydrate taste function and its association with food consumption and BMI
Secondary ID [1] 287038 0
NIL
Universal Trial Number (UTN)
NIL
Trial acronym
NIL
Linked study record

Health condition
Health condition(s) or problem(s) studied:
obesity 295505 0
Condition category
Condition code
Diet and Nutrition 295764 295764 0 0
Obesity

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Participants will be required to visit the Centre of Advanced Sensory Science laboratory, Deakin University for at least 17 times (maximum of 7 times per types of carbohydrate).

Participants may experience:
Visit 1:
Food consumption and anthropometry. Participants will be asked to complete a Cancer Council food frequency questionnaire, a 4-day diet diary, and a 3-factor eating questionnaire at home within 1 month of the sensory tests. Height, weight, waist circumference will be measured at baseline. Weight and waist circumference will be measured again at the end (final session).

Visits 1-2:
Determination of taste thresholds for the five basic tastes. Participants will be presented with a series of eight solutions for each tastants (sweet, sour, bitter, salty and umami), which will be arranged in ascending order of concentration. Participants will be asked to sample each solution, expel it after 10 seconds and then describe the taste of the solution. The process will be repeated twice (for visit 1-2) and will take approximately 1 hour 30 minutes for each visit.

Visits 3:
Suprathreshold (sufficient strength or quantity to produce a perceptible physiological effect) taste intensity perception for the five basic tastes.
Subjects will be given a brief training session in the use of gLMS (General Labelled Magnitude Scale) (in ascending order). gLMS is a scale consists of a vertical line, used to measure perceived taste intensity. To test for intensity perception of the five basic tastes (bitter, salty, sweet, sour, umami), participants will be presented with numbered trays that contained 4 randomized solution for each taste quality (15mL each). Participants were instructed to held in each of the solutions in the mouth for at least five seconds and expectorate. Participants were then required to rate the taste intensity perception on a computerised gLMS. Participants were also instructed to rinse their mouth for five seconds with filtered deionised water between samples. Solutions will be presented in randomised order. The minimum and maximum concentrations of solutions will range from 0.04g/L-63.1g/L

This will be repeated twice (for visit 3). Visit 3 will take about 50 minutes, depending on their taste sensitivity.

Visits 4-10; 11-17:
Detection thresholds for maltodextrin and inulin.
Each participant will be blinded (they will not know which carbohydrate they are tasting). Detection thresholds for carbohydrates (maltodextrin, inulin) will be tested using ascending triangle forced-choice procedure. Participants will be provided with three 25 mL samples: two controls (filtered deionised water solutions) and one containing carbohydrate (maltodextrin or inulin), per set, in ascending order from the lowest to the highest concentration. Participants were instructed to rinse their mouths for five seconds with filtered deionised water before beginning the task and between each sample set. Detection thresholds for each sweetener or polysaccharides was defined as the concentration of carbohydrate required for a participant to correctly identify the sweetened or polysaccharide sample as ‘odd’ from the two control samples, in three consecutive sample sets at one concentration level (Meilgaard et al., 2007).

Each visit will take about 10-20 minutes, depending on the sensitivity of the individual.
Each session will be separated by a minimum of 1 hour. The minimum and maximum concentration of solutions will range from 0.04g/l-63.1g/L
Intervention code [1] 292245 0
Not applicable
Comparator / control treatment
nil
Control group
Uncontrolled

Outcomes
Primary outcome [1] 295472 0
Possible associations between carbohydrate taste sensitivity (less sensitive or more sensitive), and its association with dietary consumption.
Mean taste thresholds for carbohydrates will be determined. Correlations between mean thresholds with dietary consumption (from 7 day diet diary and Cancer Council Food frequency questionnaire) will be used to determine if there are any associations between carbohydrate taste thresholds with food dietary consumption.
Timepoint [1] 295472 0
Assessed once participants have completed the 17 visits
Secondary outcome [1] 315657 0
Possible associations between carbohydrate taste sensitivity (less sensitive or more sensitive), and its association with body mass index.
Mean taste thresholds for carbohydrates will be determined. Correlations between mean thresholds with body mass index (anthropometry measurements- heigh, weight, and waist circumference) will be used to determine if there are any associations between carbohydrate taste thresholds with body mass index.
Timepoint [1] 315657 0
Assesed once participants have completed the 17 visits.

Eligibility
Key inclusion criteria
over the age of 18 years of age and below the age of 85 years.
Minimum age
18 Years
Maximum age
85 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
smokers, pregnant or lactating, known allergies towards any food used in the study to assess taste thresholds

Study design
Purpose
Natural history
Duration
Cross-sectional
Selection
Convenience sample
Timing
Prospective
Statistical methods / analysis
Information collected from participants will be used to:
1. A sample size of 30 participants was chosen in line with the central limits theorem to approximate a normal population distribution (Field, 2009).

2. Determine taste thresholds for carbohydrates (inulin and maltodextrin). Correlations between mean thresholds with BMI and food consumption (dietary pattern) will be used to determine if there are associations between carbohydrate taste thresholds with food consumption and BMI.

3. Information concerning participant's food consumption and food behaviour will be used to evaluate differences between subject's thresholds.

Recruitment
Recruitment status
Active, not recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment postcode(s) [1] 9919 0
3125 - Burwood

Funding & Sponsors
Funding source category [1] 291589 0
University
Name [1] 291589 0
Centre of Advanced Sensory Science/ School of Exercise and Nutrition Sciences, Deakin University
Address [1] 291589 0
221, Burwood Highway, 3125, Burwood, VIC
Country [1] 291589 0
Australia
Primary sponsor type
University
Name
Centre of Advanced Sensory Science/ School of Exercise and Nutrition Sciences, Deakin University
Address
221 Burwood Highway, Burwood, VIC 3125
Country
Australia
Secondary sponsor category [1] 290262 0
None
Name [1] 290262 0
Address [1] 290262 0
Country [1] 290262 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293120 0
Deakin University Human Ethics Advisory Group (HEAG)
Ethics committee address [1] 293120 0
Deakin University
221, Burwood Highway, Burwood, 3125, VIC
Ethics committee country [1] 293120 0
Australia
Date submitted for ethics approval [1] 293120 0
27/10/2014
Approval date [1] 293120 0
06/11/2014
Ethics approval number [1] 293120 0
HEAG-H 182_2014

Summary
Brief summary
The aim of this project is to investigate if humans are able to detect small amounts of carbohydrate orally and investigate links with dietary consumption and weight. Over the past decades, behavioural studies demonstrated that rats are very attracted to starch and that starch is preferred to sucrose at low concentrations, suggesting that rats have different taste receptors for sucrose and starch. Carbohydrates, in the form of sugar and starch, represent a major source of food energy. Except for some fruits, plants contain much more starch than sugar, but it is sugar with its sweet taste that is the most sought after carbohydrate. Compared to sugar, starch is rather bland to the human palate, and has been assumed to be tasteless for other animals as well. However, in the past decades, studies using animal models reported that rats are very attracted to the taste of maltodextrin (starch). The results of these studies suggest that starch and sucrose stimulate different taste qualities, indicating there is an independent taste receptor for polysaccharides.

Recent studies investigating carbohydrate sensing in the human oral cavity through exercise performance have also found that exercise performance significantly improved after participants rinsed their mouth with solutions containing maltodextrin (see review by e-Silva et al., 2014). The results suggest that there may be an independent mechanism and pathway for oral carbohydrate detection, but as yet, there is not method for assessing carbohydrate detection thresholds in humans.

A total of 30 people will participate in this project and subjects must be over the age of 18 years. It is also preferred that subjects are non-smokers.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 58574 0
Prof Russell Keast
Address 58574 0
Centre of Advanced Sensory Science, Deakin University
221 Burwood Highway, Burwood, 3125, VIC
Country 58574 0
Australia
Phone 58574 0
+61 3 92446944
Fax 58574 0
Email 58574 0
russell.keast@deakin.edu.au
Contact person for public queries
Name 58575 0
Miss Julia Low
Address 58575 0
Centre of Advanced Sensory Science, Deakin University
221 Burwood Highway, Burwood, 3125, VIC
Country 58575 0
Australia
Phone 58575 0
+61 3 92517247
Fax 58575 0
Email 58575 0
yqlow@deakin.edu.au
Contact person for scientific queries
Name 58576 0
Prof Russell Keast
Address 58576 0
Centre of Advanced Sensory Science, Deakin University
221 Burwood Highway, Burwood, 3125, VIC
Country 58576 0
Australia
Phone 58576 0
+61 3 92446944
Fax 58576 0
Email 58576 0
russell.keast@deakin.edu.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary