Subjective Evaluation - PART 3 Flashcards
What is the goal of Sensory Evaluation Methods?
Match the right test/method with the right question
3 general methods that answer questions in sensory evaluation
- discrimination tests
- descriptive analysis test
- affective/hedonic tests
What type of test: are two products different from one another?
Discrimination test
Advantage of discrimination test
Quick and simple
Limitation of discrimination test
Limited results—only yes or no
Basic setup of discrimination tests
- 25 to 50 panelists
- screening for acuity (sharpness of perception i.e. color blindness, sensitivity of tongue and nose)
- triangle, duo-trio or paired comparison tests
How is analysis done in discrimination tests?
Frequency of yes and no; refer to statistical table to determine if significant or not
What is the triangle test?
Choose sample that is most different
What is duo-trio test?
Choose sample that matches the reference
Why is it called duo-trio?
Duo: two samples are compared
Trio: reference is added
What is paired comparison test?
To determine which sample has better specified quality (i.e. sweetness)
What type of test: How do products differ in all sensory attributes?
Descriptive tests
Advantage of descriptive tests
Detailed quantitative information
Limitation of descriptive tests
Time consuming
Basic setup of descriptive tests
- 8 to 12 trained panelists
- screened for acuity
- asked to rate intensity for all sensory attributes
How is analysis done in descriptive tests?
T-test or ANOVA to determine if statistically different
What does panelist training mean for decriptive test
- trained means they are able to evaluate in a similar way
- Panelists must have same answers (i.e. sweetness of sugar of 10%)
True or False: Descriptive tests uses booths
False: only use long table with equipment and interact with everyone
What test/analysis is the only one with panel interaction?
Descriptive analysis
How is the sample ballot for descriptive tests done?
- all attributes encountered are listed down and rated each
What type of graph is used for analysis in descriptive tests and why?
Spider graph to easily show which attributes differ
True or false: Product advertisements that use sensory qualities to advertise are expected to conduct descriptive analysis
True; to have proof or backup for their claims but not all companies have sensory teams
What type of test: Are the products liked?
Consumer Acceptance Tests
Advantage of consumer acceptance test
Provides essential information if they like it or not
Limitation of consumer acceptance test
Difficult to get a representative sample of consumers
Basic setup of consumer acceptance test
- 75 to 150 consumers per test
- screened for product use (do they buy the product? How often?)
- asked degree of liking or preference questions
Basic setup of consumer acceptance test
- 75 to 150 consumers per test
- screened for product use (do they buy the product? How often?)
- asked degree of liking or preference questions
How many points is the hedonic scale?
9 points
What type of scale is used in consumer acceptance tests?
Hedonic scale
What scale is used if children are evaluators?
Smiley scale
It is the “pepsi challenge” test used in marketing research
Preference test
Flow of product testing in food companies
Product/Concept > prototype > testing > modified prototype > verification > final product
Tests used for prototype and verification in product testing
- consumer affective
- descriptive/physicochemical measurements
When to use discrimination test in product testing?
Use if an attribute needs to be modified
