Discrimination testing Flashcards
What are the 3 sensory techniques?
Discrimination test
Descriptive test
Consumer test
What is the use of a discrimination test?
Find a sensory difference between 2 or more products
What are discrimination tests used for?
Screening and training
Determine sensitivity threshold
Investigating effects of ingredient changes
Traits
What are the 4 different overall discrimination tests?
Triangle test
Duo-trio test
Tetrad
Difference from control
What are the 2 attribute discrimination tests?
Paired comparison
Ranking test
What is a triangle test?
Two identical samples and one different, assessor selects different one
Advantages of triangle test
Less assessors
Statistically robust
Disadvantages of triangle test
More comparisons
Equal amount of samples
Harder with carry-over effect
What is the duo-trio test?
Assessor is given reference and matches it with 2 coded samples
Advantages of duo-trio test
Can use with different amounts of sample
Less comparisons
Can be done with carry-over effects
Disadvantages of duo-trio test
More assessors
Less statistically robust
What is the tetrad test?
4 samples
2 of one product and 2 of another
Assessors divide samples into 2 for similar attributes
Advantages of tetrad test
Requires psychological decision making
Less assessors
Disadvantages of tetrad test
More comparisons
Harder with carry-over
What are the 3 other discrimination tests?
Two-out-of-five
Same or different
A-not A
What is a paired comparison test?
Determine difference between 2 products with specific attribute
What is the procedure of paired comparison tests?
2 coded samples where assessor determines which has greater intensity
What are multi product discrimination tests?
Determine difference between 3 or more samples with specific attribute
When are multi product discrimination tests used?
When interested in size of difference and batch-to-batch variation
Why is a choice forced in discrimination testing?
Third option invalidates statistic
Picking the difference
