Macrowine 2021
IVES 9 IVES Conference Series 9 Sensory impacts of the obturator used for the Chasselas: study over the time

Sensory impacts of the obturator used for the Chasselas: study over the time

Abstract

Many parameters affect the organoleptic characteristics of wine: internal parameters like the chemical composition or polyphenol content and external as for example storage conditions or the type of obturator. The aim of this study was to characterize sensorally the impacts of several type of obturator on a white wine: Chasselas. To determine the organoleptic characteristics of this wine, a quantitative descriptive analysis could be used. But rapid sensory methods were preferred in this project. Indeed these methods are an appropriate alternative to conventional descriptive methods for quickly assessing sensory product discrimination. As these methods gain in popularity, assessments of their discriminability and reproducibility in food applications are increasingly needed. Some studies have found that the Napping method could best accentuate qualitative sample differences, whereas the Flash Profile provided a more precise product description on quantitative differences between products. Others projects showed that Flash Profile and conventional profiling are very close in terms of characterisation. In the aim to determine the impact of the obturators on the sensory characteristics of wine, several rapid sensory methods were used. “Rapid methods of sensory profile” like Flash Profile or Napping were done and “classic” discriminative tests like triangular or two-out-of-five tests. The complementarity of these methodologies provide global results on the sensory impacts of the obturators. This project was realized with the panelists of Changins. A total of five degustation was done. The first was done at the bottling (t+0 month) and the following at t+3 months, t+9 months, t+16 months and finally at t+22 months. Four types of obturator were used: a technical obturator, two types of synthetic obturator and a screw capsule. At t+16 months, Napping and Flash Profile have shown a lower variability of organoleptic characteristics between the bottles with the technical obturator and the screw capsule. Finally, the output of these methods were quite similar but the amount of information obtained from each methodology vary. At t+22 months, no significant difference were observed with the discriminative tests between the synthetic obturators and the screw capsule. Additional sensory tests and a largest interval between bottling and tasting could confirm these observations. A study on the relation between the sensory evaluations and analytical analysis of these wines could be pertinent and complementary of the results presented here.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Pierrick Rebenaque*

*HES-SO

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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