Descriptive Analysis

Advantages of descriptive tests

-Detailed quantitative information -Provides a "picture" of the food -Useful as a control for future research -Can relate to instrumental measures

Judge Selection

-Goal: 8-12 panelists who are screened for acuity and able to participate -Able to participate -Time and energy to do the task -Asked to rate intensity for all sensory attributes usually using unstructured line scale (VAS)

Criteria and Assessment of Judge Performance

-Include "test" samples into the set to determine judge accuracy and validity -Monitor how well each judge's scores fit with the group -Use of standard deviation

Panel Training

-Panelists are trained to evaluate products similar to how an instrument would give a reading -In essence, the panelists are calibrated so that they have an understanding of each attribute and the range of intensity -Physical references are often used for standardization

Data Analysis

-Statistical analysis is done to determine if means are statistically different -Put into "Spider Charts" -Plot the average score for each attribute onto a graph -Connect the attributes by category

Limitations of descriptive tests

-Time consuming -Not related to consumer acceptability -Dependent on panel consistency

Lexicon: Generation, Definitions, and References

-Use words that have specific meaning -The meanings are determined and agreed upon by the group -Often includes intensity and order of perception -Having a physical reference is very helpful

What is Descriptive Analysis?

-Uses highly trained, sensitive judges to describe and quantitatively evaluate a sample -Selects a common vocabulary (lexicon) to paint a picture of a sample's (product) sensory attributes

Steps in Descriptive Analysis

1. Judge Selection 2. Lexicon: Generation, Definitions, and References 3. Scale Design 4. Panel Training 5. Criteria and Assessment of Judge Performance 6. Conducting the Test 7. Data Analysis and Reporting

Types of Descriptive Analysis

Quantitative Descriptive Analysis™ Sensory Spectrum ™ Flavor Profile ™ Texture Profile ™ See Sensory Eval Guide in Req'd Readings -Recommend hybrid technique designed to meet the test purpose -All use the same 7 steps

Spider Chart

The intensity of each sensory attribute increases outward radially from a central point

Purpose of Descriptive Tests

What are the sensory characteristics of a product and how do they differ in intensity and quality?