Macrowine 2021
IVES 9 IVES Conference Series 9 Correlations between sensory characteristics and colloidal content in dry white wines

Correlations between sensory characteristics and colloidal content in dry white wines

Abstract

Must clarification is an important step occurring just after grape extraction in the elaboration of white wine, consisting in a solid-liquid separation. Traditionally, low must turbidity, around 50-150 NTU, is generally reached in white winemaking in order to prevent reductive aromas and facilitating alcoholic fermentation. Alternatively, a higher turbidity (300 NTU or above) can be sought for reasons such as a better expression of grapes identity (terroir), or for getting a must matrix that could supposedly lead to wines having greater ageing potential. In any case, must clarification has an impact on the juice content and subsequently on the wine composition and sensory attributes. However, correlations between the macromolecular content of dry white wines and their sensory perceptions were never reported so far. In order to investigate the links existing between the chemical composition of dry white wines and their sensory characteristics, Chardonnay wines from Burgundy, obtained from musts with three levels of clarification (Low, Medium and High) and for two vintages (2009 and 2010) were analyzed. Three bottles per turbidity level were opened in 2015 in order to evaluate their organoleptic characteristics by a trained sensory panel composed of 31 students from the Institut Universitaire de la Vigne et du Vin at Dijon, France. Reductive and/or oxydative states of each wines had to be ranked on a scale of 0 to +5. Results were statistically analyzed and correlated to both a target analysis of fluorescent wine compounds including polyphenols and proteins, and an unsupervised analysis by Excitation Emission Matrices of Fluorescence (EEMF). Putative known and unknown molecular markers for the distinct redox states could be proposed, as a function of vintages.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Article

Authors

Christian Coelho*, Jordi Ballester, Maria Nikolantonaki, Mathilde Magne, Régis Gougeon

*Université de Bourgogne, IUVV

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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