Why a Pivot profile^©?

This descriptive test is recommended when one wishes to characterize and discriminate between products without having prior information on these products, or when one does not want to restrict this description to questions of intensities.

Indeed, this test is used in exploratory approaches to obtain both qualitative results on the nature of the sensory descriptors, and quantitative results on the evaluation of the main characteristics.

The questions this test can answer are for example:

“How are these different products characterized?”

"By what characteristics, these products are mainly distinguished",

“What are the effects of this or that treatment? » …

Prerequisites of a Pivot profile^© ?

Unlike a QDA profile, the constraints are much lower in terms of the nature and number of panelists; the subjects do not require any special education or training for this type of test; indeed, the test will take into account the variability and the richness of perception and sensory expression of each participant, whether they are very expert, qualified or naive. It will only be necessary to provide at least a jury of ten people, with no upper limit. The products are not subject to any constraints either, they can be from 2 to 100, because the tests will always be carried out in pairs, and therefore without any notion of sensory saturation, nor even any constraint on the nature of the products, scalable or not, during the evaluation.

Principle of a Pivot profile^© ?

Each subject will be asked to compare each product to be evaluated, in pairs with the same average product, called 'the pivot'.

The panelists will then have to indicate which are the qualifiers perceived “less…”, and those perceived “more…” for this product, compared to the 'pivot' product. These qualifiers will then be counted and reconciled by synonyms for the entire panel in order to bring out the differential characteristics, and associated with a frequency; this processing therefore allows a quantification of these criteria for each product.

The pivot product will either be made up from the products to be analyzed by mixing them in equal parts in order to constitute the most average product (for products in the form of liquids or powders), or selected as being the most average product at the within the group of products to be analysed.

It will be possible to refer, for the description of this method, to the publication: « Pivot^{© Profile: A new descriptive method based on free description - Bertrand Thuillier et al. , 2015 ".}

Results of a Pivot Profile^© ?

The results are quite similar to a QDA profile by substituting the averages by frequencies, with for example tables and graphs of frequencies, multi-dimensional representations using CFA (Correspondence Factor Analysis), but also with hypothesis tests to identify if such a product is significantly different or not with another product using 2 to 2 comparisons. Raw data per judge and per product can also be generated to be processed in a similar way to an analysis classic data.

Advantages and Limitations of a Pivot Profile^© ?

This method constitutes a very open and exploratory approach to describe products in a very discriminating way, by this very simple question of qualification of the differences between two products; this questioning can approach the very principles of sensory perception based on a principle of perceptual contrast. This also allows free expression to fully take into account the inter-individual variability, voluntarily erased or reduced in the classic tests in which the answers are closed and identical for all the subjects. This openness also allows questions from experts and/or consumers.

The limits lie more in the singular aspect of the measurement which is due to the nature of the panel used; the description will depend on the subjects questioned for its richness of expression and its ability to discriminate, but this ultimately remains a feature specific to the nature of sensory measurement.

Additional analyzes of a Pivot profile^© ?

In a similar way to QDA profiles, the results of these tests can be advantageously associated by their great descriptive richness and their openness, with instrumental or formulation data, in order to formulate hypotheses as to the origin of perceptions with this or that type of molecule or product.