SENSORY EVALUATION: SENSORY PANELS
Diagram
An instrument or a jury of buyers
Trained panel
A small group, trained for weeks or months, that measures the food like an instrument: same words, same scales, same way every time.
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Consumer panel
A large group of ordinary buyers, not trained, that says what they like and whether they would buy the food.
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Different jobs
The trained panel describes the food; the consumer panel judges it. Neither can do the other’s job well.
Figure 1: A trained panel measures; a consumer panel likes or dislikes. Drawn in our own style from the descriptive analysis panels and the consumer field tests chapter (p. 480) of Lawless and Heymann, Sensory Evaluation of Food.
Introduction
A trained panel and a consumer panel are both groups of people tasting food, but they do different jobs. A trained panel measures attributes objectively, like an instrument, while a consumer panel reports liking, like a jury of buyers. Lawless and Heymann cover descriptive analysis panels and consumer field tests and questionnaire design (p. 480).
The core difference is training and purpose: the trained panel is trained to measure, and the consumer panel is untrained and asked only what it likes.
Quick comparison
Table 1: Trained panel compared with Consumer panel
| Aspect | Trained panel | Consumer panel |
|---|---|---|
| Size | Small, usually around 8 to 12 people | Large, often 50 or more people |
| Training | Long training, weeks or months, in vocabulary and scales | None |
| What they do | Measure the intensity of specific attributes | Say how much they like the food and whether they would buy it |
| Vocabulary | A shared vocabulary, agreed by the panel | Their own words, as ordinary buyers |
| Repeatability | High: the same panel gives the same result on another day | Low for one person, steady only as an average of many |
| Selection | Chosen for sensitivity and ability to describe what they sense | Chosen to match the buyers the product is made for |
| Cost | Costly to train and to keep, cheap to run per test | Cheap per person, costly in numbers |
| Use | Describing products, finding faults, guiding recipes | Choosing between products, testing acceptance, forecasting sales |
| Result | A profile of the product | A liking score and a buy or not buy answer |
| Can they swap roles | No: a trained panellist is trained not to judge liking, and a consumer cannot measure like an instrument | No: the roles need different people |
Scientific explanation
Definition
A trained panel is a small group of people trained to measure the sensory attributes of food: they learn a shared vocabulary, agree on what each word means, and rate each attribute on a scale, so they work like a measuring instrument. A consumer panel is a large group of ordinary buyers, not trained, who taste food and report their liking and their buying intent.
Lawless and Heymann cover descriptive analysis panels for the trained side, and consumer field tests and questionnaire design (p. 480) for the consumer side.
Working principle
A trained panel works by calibration: training aligns the panellists, so one panellist’s 5 for sweetness means the same as another’s 5, and the panel can repeat the result on another day. The panel is treated as an instrument, and its performance is checked and retrained.
A consumer panel works by numbers: one consumer’s liking is personal and variable, but the average of many consumers is steady, and it predicts what buyers will do. The panel is treated as a sample of the market, so it must match the buyers the product is made for.
Apparatus
Both need a sensory test room with separate booths, coded samples, water and plain crackers to cleanse the palate, and ballots. The trained panel also needs reference standards for each attribute, so the panel can calibrate itself, and the consumer panel needs a questionnaire that asks about liking and buying intent.
Measurement procedure
For a trained panel, panellists are recruited, screened for sensitivity, trained in the vocabulary and the scales, and then tested regularly to check their performance. For a consumer panel, buyers matching the target market are recruited, served coded samples in a balanced order, and asked to rate liking and buying intent on a questionnaire.
The books used here describe the panels and their recruitment and training; they do not give one single standard procedure for both, because the two panels are built and run differently.
Factors affecting readings
For a trained panel, the training and the retraining matter most: without them the panel drifts and the results cannot be trusted. For a consumer panel, the match to the market matters most: a panel of the wrong buyers gives the wrong liking scores. Fatigue and carryover matter for both.
Formulas and calculations
The books used for this article give no formula for this comparison, so none is given here. The comparison is qualitative: it rests on definitions, materials and method, not on a calculation.
Industrial applications
- A trained panel is used to profile a new product, so the recipe can be aimed at the right attributes.
- A trained panel is used in quality control, to find small faults before the buyer does.
- A consumer panel is used to test whether buyers will accept a new product.
- A consumer panel is used to choose between recipes, by liking scores.
- Both are used together in product development: the trained panel shapes the product, and the consumer panel judges it.
Advantages and limitations
- Trained panel, advantage: steady, repeatable measurement, like an instrument, so small differences can be found.
- Trained panel, limitation: costly to train and keep, and it cannot say whether buyers will like the product.
- Consumer panel, advantage: measures real liking and buying intent, which is what decides sales.
- Consumer panel, limitation: needs many people for a steady result, and cannot say what is wrong with a product.
FAQ
Can I use my own staff as a consumer panel?
Only with care: staff know the product and may not match the buyers it is made for. A consumer panel should match the target market, not the office.
How long does it take to train a panel?
Weeks or months: panellists must learn the vocabulary, agree on what each word means, and practise rating on the scales until they agree with each other.
Can a trained panellist also be a consumer panellist?
Not in the same test: training changes how a person tastes, so a trained panellist no longer tastes like an ordinary buyer. The roles need different people.
Why do consumer panels need so many people?
Because liking varies from person to person. One consumer’s score means little, but the average of 50 or more is steady enough to trust.
What happens if a trained panel disagrees?
The panel is retrained: the panellists taste reference standards together, discuss the differences, and practise until they agree. A panel that cannot agree cannot be used.
References and further reading
- Harry T. Lawless and Hildegarde Heymann, Sensory Evaluation of Food: Principles and Practices, Springer, 1999 (Google Books page read)
- FTN books on disk: Sensory Evaluation Practices; Sensory Evaluation Techniques; Sensory Panel Management: A Practical Handbook for Recruitment, Training and Performance
