CORNELL
U N I V E R S I T Y 		16Food Science 430
Wine is chemistry, biology and psychology!

Calendar

Primer
Psychophysics Slides

Reading: Jackson pp 564-590
Sensory Testing Methods
by Harry T. Lawless

DISCRIMINATION TESTING

Basic question: Are two products different?

Typical setup:

    25 - 50 panelists per test, screened for acuity
    triangle or duo-trio procedure, run in replicate
    simple analysis via significance tables

Advantages:
    quick, simple both in procedure and analysis
    can be easily worked into a program, re-use panelists
    only a few discriminators (minority) yeild significant results

Liabilities:
    limited information (yes/no)
    not suitable for quality variation problems
    test lacks sensitivity if not focussed

Costs:
    panel screening, panel incentives*
    technician time in setup, recruiting* , analysis*, reporting
    some products may require controlled facility (odors, noise, etc.)

Shortcuts:
    can perform in conference room with dividers
* may be minimal

DESCRIPTIVE ANALYSIS

Basic question: How do products differ in all sensory attributes?

Typical setup:

    8 - 12 panelists per test, screened for acuity, moitivation and trained
    rating scales for all sensory attributes, run in replicate

Advantages:
    detailed information on all product attributes; quantitative
    can be correlated with consumer opinion, instrumental measures
    related to ingredient, processing or packaging variables

Liabilities:
    time-consuming and expensive
    may not capture integrated impressions
    panel may be over-analytical
    intensity scaling model may not be useful

Costs:
    panel screening, panel training, panel incentives
    panelist time away from workm (if employees)
    technician time in setup, recruiting , analysis, reporting
    some products may require controlled facility (odors, noise, etc.)
    computing capabilities a must

Shortcuts:
    some simple products may require minimal training
    consensus procedures may avoid data handling

CONSUMER ACCEPTANCE TESTING

Basic question: Are products liked?

Typical setup:

    75 - 150 consumers per test, screened for acuity
    scaled acceptance (degree of like/dislike) or preference-choice

Advantages:
    provides essential information; ³bottom line²
    can identify liking/disliking segments
    can be related to descriptive profile, other variables in optimization

Liabilities:
    consumer vocabulary fuzzy
    representative samples can be a problem
    preference may be ambiguous

Costs:
    consumer recruiting, qualification as users/likers
    technician time in setup, recruiting , analysis, reporting
    computing required if long questionnaire, large sample
    some products may require controlled facility (odors, noise, etc.)

Shortcuts:
    can perform with employees or community groups

  FS430 Revised 3.7.01