Red wine astringency: correlations between chemical and sensory features

Astringency is a crucial sensory attribute typically described as the drying and/or puckering sensation occurring after the consumption of tannin-rich foods and beverages.

In this study, thirty-seven red wines from different varieties, origins and styles were evaluated, analyzing both chemical and sensory features. Principal Component Analysis was used for dimensionality-reduction and for correlating selected chemical parameters against astringency.

The results showed that tannin content was the most important chemical parameter influencing overall astringency but more clearly the dryness sub-quality, followed by pH, titratable acidity and alcohol content.

A further evaluation compared the performance of two widely employed methods for tannin determination (i.e., methylcellulose and Harbertson-Adams assays), as predictors of wine astringency, showing differences as astringency estimators; with lower variability of HA in the low and mid tannin concentration range and MCP at high tannin concentrations. Interestingly, the fitted curve for HA vs. astringency exhibited a sigmoidal behavior, where diversion from linearity might be due to a protein precipitation threshold, as well as a maximum tannin concentration beyond which sensorial saturation may be reached.

Poster presented at the Macrowine Virtual Congress (23-30 June 2021)

For more information:
Carolina Pavez, Beatriz González-Muñoz, José A. O'Brien, V. Felipe Laurie, Fernando Osorio, Emerson Núñez, Ricardo E. Vega, Edmundo Bordeu, Natalia Brossard, Red wine astringency: Correlations between chemical and sensory features, LWT, Volume 154, 2022, https://doi.org/10.1016/j.lwt.2021.112656.