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Abstract: Although visually easily detected, the impact of olfactory and gustatory CO2
in champagne were still largely unknown. Taking into account bibliography and the many variability factors,this have
prompted us to start working with water, environment simpler than champagne, to compare pairs of perceived
intensities of two states, with CO2 and CO2-free, before switching to champagne and
characterization of perceptions. To this end, we used free sensory descriptions as current sensory techniques
cannot obtain reliable descriptions of smell due to the very rapid developments of wines by the effect of outgassing,
and very significant Inter-individual perceptions differences.
We identify three main effects and their physiological origins:
As CO2 is part of a champagne, the latter with CO2, are defined as 'pleasant' and 'fresh' nose with a 'attaque_ferme' (firm attack), and 'finale_longue' (long final). The absence of CO2 produces a negative hedonic perception with terms like 'evolution' (passed) nose, 'manque_dacidité' (lack of acid), 'bouche_grasse' (fat mouthfeel), 'bouche_plate' (flat mouthfeel), 'Alcohol', 'watery' and 'finale_alcooleuse' (alcoholic final).
These results also showed all the variability of the collected sensory text, its specificity, and deficiencies of sensory metrology dealing with products aromatically complex, and evolving, then we propose a new descriptive general model, the Pivot© Profil, based on pair comparisons.
[ Download the method in French ]
The principle: Pivot© Profile (Thuillier, 2007) is based on a free expression of the difference between two products, one is regarded as pivot, and will be always present for all comparisons, then these adjectives collected in a much more direction and in a less direction are counted (additions to the 'more', and subtractions for 'less') by assessed product, after being grouped with possible appropriate grids of synonyms. Calculations are applied on these counts in order to then identify the characteristics of each product by considering the terms of the whole judges per product, it is also possible to identify the characteristics of each of the judges considering the terms of the whole products per judges.