Samenvatting Sensory Science I: Principles of Sensory Science (HNE30506)
College 1 + 2 – Selection and training of sensory panels
Studying material: chapter 3 – Principles of good practice. 3.5 Panelist consideration.
Central questions
- Why select sensory subjects? – in sensory test we want them to be good in a
particular task so we need to test who are well-fitted to do the task.
- How to select sensory subjects?
- How to train sensory subjects?
- When is the panel trained enough?
- Check performance over time?
A sensory test is expensive due to the paying of participants.
Analytical sensory panels
Recruitment
Internal or external? – internal is within an organisation, external is from anywhere. In
practice it does not always work with internals because they know too much.
Age 20-55 – already developed associations and tastes. After 55 they might not
perform well anymore (less sensitive).
Selections rule of thumb: test twice the number of subjects needed – only half will
really perform the test.
Announcement.... all media?
Panel selection – Questionnaire
- Personality
Be able to work in a team
“Cosmopolitan” preferences
Positive not over-bearing
Good listener and communicator
Committed and flexible
- Health
General good health condition
Documentation of any health restrictions (medication, allergies, pregnancy, false
teeth, ..)
- Availability
Panel selection – tests for sensory ability
Type of tests
Basic tastes taste detection and recognition
Rapid taste test: you can try on left/right/front of the tongue if they taste the basic
tastes
Taste intensity ranking JND taste ca. 30% concentration step
Odour recognition e.g. Sniffin’ sticks, ISO, UPSIT
Threshold, Discrimination and Identification (TDI) testing: score! – this score
should be within a certain range to perform in a panel
Odour memory
Naming/creativity e.g. sensory properties of a product – big description about
what you perceive
Colour blindness various tests available
, Other observations
Social ability – behaviour in a group
Not necessary to do all tests at all times. Basic tastes is a test which is done in most times.
Panel orientation
- General training: familiarisation with test protocols, discrimination tests, intensity
scaling
- Product specific training
Selection and training of subjects
1. Group of inexperienced people (intern/extern)
2. Basic selection
Questionnaires (health, availability, …)
Tests on taste/ odour discrimination, recognition, thresholds, memory and colour
blindness
3. Task oriented selection
Discriminative tests
Linguistic abilities
4. Training for a descriptive panel
Discriminative tests
Development of sensory descriptors
Reference materials
Training on intensity scale/ repeatability
In a descriptive analysis you need to do more than these 4 steps
Analytical sensory panels
Monitoring of performance
Inter individual variation
Intra individual variation
Sequential analysis – long-term performance
How is the performance? Did it change over time (especially important in elderly
with probably decreased sensitivity)
Feedback on performance to individual or panel
Motivation and maintenance
Degree of difficulty (novice)
Test frequency
Reward and attention
Feedback after test
Feel good factor – challenges - Important to invest time and money in this
Agreement before assessment
No eating and drinking before
No smoking
No perfume
Indicate it having a cold, feeling tired
Punctuality
Agreement during assessment
Quiet and no communication with others
No eating
Follow instructions
, Role of panel leader
- Type of roles
Passive facilitator (e.g. QDA) – no opinion, no guidance
Directive leader (e.g. Spectrum)
- Personal characteristics
Non-judgemental/ opinionated
Sensitive and assertive, but diplomatic
Leading panel discussions but active listener – not telling own opinion!
Recognises and guards against moderator bias
Ability to motivate panel
Descriptive sensory analysis
Study material: chapter 10 descriptive analysis.
Descriptive sensory analysis = a method aiming to provide a quantitative measure of the
sensory properties for a set of products
A number of different approaches:
Trademarks (QDA and Spectrum) – follow particular ways to do descriptive
analysis
Speed versus accuracy
Relations to instrumental measures
Why using descriptive sensory analysis?
Product reformulations
New product development
Quality control
Acceptability to specified target
Calibration of instrumental methods
Brand mapping (e.g. identifying sensory niches)
Consumer preference mapping
Research: understanding relationships between product/ process/ production
properties and perceptible properties
Main differences between methods
Differences between methods:
- Generation of sensory
descriptors
- Degree of subject training
- Use of reference materials and scaling
History of descriptive analysis methods: lots of different methods, nowadays we use fast
methods like Flash Profile.
Methodological categorisation Descriptive Sensory Analysis:
1. Verbal elicitation methods
a) Consensus vocabulary methods – agreement on specific words to express
(descriptors)
Flavour profile
College 1 + 2 – Selection and training of sensory panels
Studying material: chapter 3 – Principles of good practice. 3.5 Panelist consideration.
Central questions
- Why select sensory subjects? – in sensory test we want them to be good in a
particular task so we need to test who are well-fitted to do the task.
- How to select sensory subjects?
- How to train sensory subjects?
- When is the panel trained enough?
- Check performance over time?
A sensory test is expensive due to the paying of participants.
Analytical sensory panels
Recruitment
Internal or external? – internal is within an organisation, external is from anywhere. In
practice it does not always work with internals because they know too much.
Age 20-55 – already developed associations and tastes. After 55 they might not
perform well anymore (less sensitive).
Selections rule of thumb: test twice the number of subjects needed – only half will
really perform the test.
Announcement.... all media?
Panel selection – Questionnaire
- Personality
Be able to work in a team
“Cosmopolitan” preferences
Positive not over-bearing
Good listener and communicator
Committed and flexible
- Health
General good health condition
Documentation of any health restrictions (medication, allergies, pregnancy, false
teeth, ..)
- Availability
Panel selection – tests for sensory ability
Type of tests
Basic tastes taste detection and recognition
Rapid taste test: you can try on left/right/front of the tongue if they taste the basic
tastes
Taste intensity ranking JND taste ca. 30% concentration step
Odour recognition e.g. Sniffin’ sticks, ISO, UPSIT
Threshold, Discrimination and Identification (TDI) testing: score! – this score
should be within a certain range to perform in a panel
Odour memory
Naming/creativity e.g. sensory properties of a product – big description about
what you perceive
Colour blindness various tests available
, Other observations
Social ability – behaviour in a group
Not necessary to do all tests at all times. Basic tastes is a test which is done in most times.
Panel orientation
- General training: familiarisation with test protocols, discrimination tests, intensity
scaling
- Product specific training
Selection and training of subjects
1. Group of inexperienced people (intern/extern)
2. Basic selection
Questionnaires (health, availability, …)
Tests on taste/ odour discrimination, recognition, thresholds, memory and colour
blindness
3. Task oriented selection
Discriminative tests
Linguistic abilities
4. Training for a descriptive panel
Discriminative tests
Development of sensory descriptors
Reference materials
Training on intensity scale/ repeatability
In a descriptive analysis you need to do more than these 4 steps
Analytical sensory panels
Monitoring of performance
Inter individual variation
Intra individual variation
Sequential analysis – long-term performance
How is the performance? Did it change over time (especially important in elderly
with probably decreased sensitivity)
Feedback on performance to individual or panel
Motivation and maintenance
Degree of difficulty (novice)
Test frequency
Reward and attention
Feedback after test
Feel good factor – challenges - Important to invest time and money in this
Agreement before assessment
No eating and drinking before
No smoking
No perfume
Indicate it having a cold, feeling tired
Punctuality
Agreement during assessment
Quiet and no communication with others
No eating
Follow instructions
, Role of panel leader
- Type of roles
Passive facilitator (e.g. QDA) – no opinion, no guidance
Directive leader (e.g. Spectrum)
- Personal characteristics
Non-judgemental/ opinionated
Sensitive and assertive, but diplomatic
Leading panel discussions but active listener – not telling own opinion!
Recognises and guards against moderator bias
Ability to motivate panel
Descriptive sensory analysis
Study material: chapter 10 descriptive analysis.
Descriptive sensory analysis = a method aiming to provide a quantitative measure of the
sensory properties for a set of products
A number of different approaches:
Trademarks (QDA and Spectrum) – follow particular ways to do descriptive
analysis
Speed versus accuracy
Relations to instrumental measures
Why using descriptive sensory analysis?
Product reformulations
New product development
Quality control
Acceptability to specified target
Calibration of instrumental methods
Brand mapping (e.g. identifying sensory niches)
Consumer preference mapping
Research: understanding relationships between product/ process/ production
properties and perceptible properties
Main differences between methods
Differences between methods:
- Generation of sensory
descriptors
- Degree of subject training
- Use of reference materials and scaling
History of descriptive analysis methods: lots of different methods, nowadays we use fast
methods like Flash Profile.
Methodological categorisation Descriptive Sensory Analysis:
1. Verbal elicitation methods
a) Consensus vocabulary methods – agreement on specific words to express
(descriptors)
Flavour profile
