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Trial registered on ANZCTR


Registration number
ACTRN12616000790448
Ethics application status
Approved
Date submitted
9/06/2016
Date registered
17/06/2016
Date last updated
23/01/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Associations between the perception of different oils, sensory detection thresholds for oleic acid and taste intensity ratings for sucrose and sodium chloride
Scientific title
Associations between the perception of different oils, sensory detection thresholds for oleic acid and taste intensity ratings for sucrose and sodium chloride in healthy adults.
Secondary ID [1] 289413 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
obesity 299083 0
Condition category
Condition code
Diet and Nutrition 299115 299115 0 0
Obesity
Neurological 299154 299154 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
In this study, detection thresholds of different sensory attributes including canola oil (triglyceride-rich), paraffin oil (triglyceride-rich), oleic acid (free fatty acid-rich) and canola oil + oleic acid (triglyceride- and free fatty acid-rich) will be determined in a repeated measure design to examine test-retest reliability and to compare detection thresholds of the four stimuli. Each of the four stimuli will be tested on 3 separate days. Hence, in total there will be 12 non-consecutive measuring days with one testing session of approximately 1 hour per day for each subject. All sessions will be held in the Deakin University Centre for Advanced Sensory Science laboratories.

To determine detection thresholds for fat and fatty acids, concentrations of canola oil (9.90, 32.69, 46.09, 65.37, 92.18, 130.10, 183.70, 259.54, 366.75, 518.10, 731.87, 1033.58, 1634.37 mM), paraffin oil (5.41, 17.88, 25.21, 35.76, 50.42, 71.15, 100.47, 141.95, 200.59, 283.37, 400.29, 565.30, 893.90 mM), oleic acid (0.02, 0.06, 1.00, 1.40, 2.00, 2.80, 3.80, 5.00, 6.40, 8.00, 9.80, 12.00, 20.00 mM) and canola oil + oleic acid (9.90+3.80, 32.69+3.80, 46.09+3.80, 65.37+3.80, 92.18+3.80, 130.10+3.80, 183.70+3.80, 259.54+3.80, 366.75+3.80, 518.10+3.80, 731.87+3.80, 1033.58+3.80, 1634.37+3.80 mM) will be prepared in a non-fat milk emulsion,
Detection thresholds will be determined using the 3-alternative forced choice method. In this method, subjects receive a set of 3 samples, one test sample containing the stimulus and two control samples. Subjects are instructed to taste and expectorate each sample and to identify the odd one out. Since samples are expectorated and the test stimuli are present in the daily diet, no washout phase is included. Concentrations are presented in ascending order. Whenever a subject’s answer is incorrect, the concentration of the test sample is increased until a concentration is reached, that can be detected by the subject. Following a correct identification of the test sample, the subject receives a new set of samples with the same concentration as correctly identified before. Whenever the subject identifies the same concentration three consecutive times in succession, this concentration is documented as detection threshold. To mask visual cues, the sensory testing is conducted under red light. To mask olfactory cues, subjects are instructed to wear a nose clip during testing.

On each of the 12 study appointments, a detection threshold for one of the four stimuli is determined. Additionally, anthropometric measurements (body weight and height) will be measured during the first study appointment to determine the subjects’ body mass index. On the second study appointment, taste intenstiy testing for sucrose (100, 200, 300 mM) and sodium chloride (100, 200, 300 mM) will take place after the measurement of the detection threshold. To control for normal taste function, subjects will recieve three different concentrations of the stimulus (sucrose/sodium chloride in randomized order). After introducing the subject to a labelled magnitude scale, they have to taste each sample and rate its intensity on this scale. Saliva samples will also be collected after the first detection threshold for canola oil is assessed to determine the level of the saliva enzyme lingual lipase which is responsible for hydrolyzing triglycerides into free fatty acids which can evoke sensory signals by interacting with fat-specific receptors.

Each testing day, subjects will report what they have eaten from the time they awoke in the morning. By evaluating these food diaries and additional questionnaires (Food Frequency Questionnaire, Food Like-Dislike Questionnaire, Visual Analogue Scales on physiological conditions such as hunger, appetite, etc.), the subjects’ eating behavior can be assessed. Additionally, conclusions about the influence of the food composition on sensory sensitivity can be drawn.
Intervention code [1] 295000 0
Not applicable
Comparator / control treatment
Detection thresholds will be determined by presenting a set of 3 samples, one test sample containing the stimuli (canola oil/paraffin oil/oleic acid/canola oil + oleic acid) and two control samples without stimulus.
Control group
Active

Outcomes
Primary outcome [1] 298589 0
Determination of detection thresholds for canola oil as a triglyceride-rich source of fat, assessed using the 3-alternative forced choice method.
Timepoint [1] 298589 0
Assessed on 3 testing sessions on 3-non-consecutive days.
Primary outcome [2] 298632 0
Examination of the reliability of detection thresholds for canola oil, assessed using the 3-alternative forced choice method in a repeated measure design.
Timepoint [2] 298632 0
Assessed on 3 testing sessions on 3-non-consecutive days.
Primary outcome [3] 298633 0
Examination of the impact of lingual lipase activity on detection thresholds for canola oil and oleic acid, assessed by collecting saliva samples on the initial measurement and determination of the lingual lipase activity.
Timepoint [3] 298633 0
Assessed once participants have completed the 12 visits.
Secondary outcome [1] 324664 0
Examination of correlations between detection thresholds for canola oil, paraffin oil, oleic acid, canola oil + oleic acid assessed by using the 3-alternative forced choice method for each stimulus and taste intensity ratings for sucrose and sodium chloride
Timepoint [1] 324664 0
Assessed once participants have completed the 12 visits.
Secondary outcome [2] 324815 0
Examination of correlations between detection thresholds of the four stimuli and BMI, assessed by using the 3-alternative forced choice method for each stimulus and by measuring body weight and height.
Timepoint [2] 324815 0
Assessed once participants have completed the 12 visits.
Secondary outcome [3] 324816 0
Examination of correlations between detection thresholds of the four stimuli and food consumption/eating behaviour, determined by using the 3-alternative forced choice method for each stimulus, food diaries and several eating-behaviour-related questionnaires (Food Frequency Questionnaire, Food Like-Dislike Questionnaire, Visual Analogue Scales on physiological states (e.g. hunger)).
Timepoint [3] 324816 0
Assessed once participants have completed the 12 visits.

Eligibility
Key inclusion criteria
aged 18-55 years, self-reported normal smell and taste function
Minimum age
18 Years
Maximum age
55 Years
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
impairments in smell and/or taste, pregnancy, lactose intolerance

Study design
Purpose
Screening
Duration
Cross-sectional
Selection
Convenience sample
Timing
Prospective
Statistical methods / analysis
The justification for the sample size of 30 subjects is based on the central limits theorem.

Information collected from participants will be used to:

1. Determine taste thresholds for canola oil, oleic acid, sucrose and sodium chloride. Correlations between mean thresholds with BMI and food consumption (dietary pattern) will be used to determine if there are associations between taste thresholds with food consumption and BMI.

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

3. Saliva samples will be taken to measure the level of lingual lipase to examine associations between taste thresholds and lingual lipase activity.

Recruitment
Recruitment status
Completed
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] 13380 0
3125 - Burwood
Recruitment postcode(s) [2] 13381 0
3151 - Burwood East

Funding & Sponsors
Funding source category [1] 293788 0
University
Name [1] 293788 0
School of Exercise and Nutrition Sciences, Deakin University
Address [1] 293788 0
221 Burwood Highway
Burwood, 3125
Victoria
Country [1] 293788 0
Australia
Primary sponsor type
Individual
Name
Prof. Russell Keast
Address
Centre for Advanced Sensory Science
School of Exercise and Nutrition Sciences
Deakin University
221 Burwood Highway
Burwood VIC 3125
Country
Australia
Secondary sponsor category [1] 292622 0
Individual
Name [1] 292622 0
Jaana Heinze
Address [1] 292622 0
Institute for Diabetes Research and Metabolic Diseases (IDM)
of the Helmholtz Center Munich at the University of Tuebingen,
University Hospital Tuebingen
Otfried-Mueller-Str. 47
72076 Tuebingen

Country [1] 292622 0
Germany

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 295223 0
Deakin University Human Research Ethics Committee
Ethics committee address [1] 295223 0
221 Burwood Highway, Burwood
VIC 3125
Ethics committee country [1] 295223 0
Australia
Date submitted for ethics approval [1] 295223 0
16/05/2016
Approval date [1] 295223 0
23/06/2016
Ethics approval number [1] 295223 0

Summary
Brief summary
Obesity is a major health issue that is currently affecting millions of people worldwide. Differences in the taste system due to genetic and dietary factors might explain why some individuals are more prone to become obese than others. There is increasing evidence that humans, apart from being sensitive for the five primary taste qualities, can also taste fat in form of free fatty acids when additional sensory cues are masked. However, in the common diet, the concentration of free fatty acids is relatively low and fat is mainly consumed in the form of triglycerides. The present study aims to determine detection thresholds for canola oil as a triglyceride-rich source of fat and to investigate the associations between individual differences in fat taste sensitivity with detection thresholds of additional sensory stimuli, diet, body mass index, and saliva composition.
In this study, detection thresholds of fat (canola oil, paraffin oil, canola oil + oleic acid) and fatty acids (oleic acid) will be determined in a repeated measure design in 30 subjects between 18-55 years. Each of the four stimuli will be tested on 3 separate days with 1 testing sessions per day. Hence, in total there will be 12 testing sessions of approximately 1 hour on 12 measuring days for each subject.
All sessions will be held in the Deakin University Centre for Advanced Sensory Science laboratories. At the initial study appointment, body weight and height will be measured to calculate the subjects’ body mass index. Saliva samples will also be collected during the first session to determine the level of the saliva enzyme lingual lipase which is responsible for hydrolyzing triglycerides into free fatty acids. Additionally, eating behavior-related questionnaires and food diaries of each testing day will be collected. Each testing day, detection thresholds of one of the four stimuli will be determined using the ascending 3-alternative forced choice method. In this method, subjects receive a set of 3 samples (one test sample containg the stimulus at a specific concentration and two control samples) and the instruction to taste each sample and to identify the odd one out.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 66586 0
Prof Russell Keast
Address 66586 0
Centre for Advanced Sensory Sciences
School of Exercise and Nutrition Sciences
Deakin University
221 Burwood Highway
Burwood VIC 3125
Country 66586 0
Australia
Phone 66586 0
+61 3 92446944
Fax 66586 0
Email 66586 0
russell.keast@deakin.edu.au
Contact person for public queries
Name 66587 0
Prof Russell Keast
Address 66587 0
Centre for Advanced Sensory Science
School of Exercise and Nutrition Sciences
Deakin University
221 Burwood Highway
Burwood VIC 3125
Country 66587 0
Australia
Phone 66587 0
+61 3 92446944
Fax 66587 0
Email 66587 0
russell.keast@deakin.edu.au
Contact person for scientific queries
Name 66588 0
Miss Jaana Heinze
Address 66588 0
Institute for Diabetes Research and Metabolic Diseases (IDM)
of the Helmholtz Center Munich at the University of Tuebingen
University Hospital Tuebingen
Otfried-Mueller-Str. 47
72076 Tuebingen
Country 66588 0
Germany
Phone 66588 0
+49 7071 29-81193
Fax 66588 0
Email 66588 0
jaana.heinze@med.uni-tuebingen.de

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