 IVES 9 IVES Conference Series 9 Phenolic, antioxidant, and sensory heterogeneity of oenological tannins: what are their possible winemaking applications?

Phenolic, antioxidant, and sensory heterogeneity of oenological tannins: what are their possible winemaking applications?

Abstract

AIM: The aim of this work was to characterize 18 oenological tannins by the polyphenolic, antioxidant, and sensory point of view. These properties have been evaluated in model wine solution as well as in red wine added with these tannins to observe matrix effects and therefore to assess their performances in a real condition.

METHODS: Polyphenolic content (A280, Folin-Ciocalteu, proanthocyanidins assay) and antioxidant properties (ABTS, DPPH, FRAP, CUPRAC) were studied in a model wine solution (12 % ethanol, 4 g/L tartaric acid, pH 3.5). Bitterness and astringency sensory analysis (Descriptive Analysis) of selected formulations (40 g/hL) was performed in water and in red wine. After 1 month, the tannin-added wines were evaluated in terms of polyphenolic content (A280), antioxidant capacity (DPPH, FRAP), total anthocyanins, and polymerized pigments.

RESULTS: Antioxidant properties of oenological tannins and their influence on wine characteristics were strongly affected firstly by their polyphenolic richness, followed by their origin. In particular, the great antioxidant capacity of hydrolysable tannins was evident in both model wine solutions and wines after one month. Ellagitannins, thanks to this property, also led to an increased percentage of wine polymeric pigments with respect to the control whereas gallotannins showed low polymerization ability. Good performances were evidenced also by Acacia tannins additions in terms of increased polymeric pigments ratio. Moreover, quebracho formulations showed the highest perceived astringency and bitterness, but only in water solutions. In the same medium, ellagitannins exhibited a low value of bitterness and astringency but, on the contrary, they were perceived as astringent in red wine highlighting a significant matrix effect.

CONCLUSIONS

Phenolic content and antioxidant properties of tannin formulations in model wines are correlated with the characteristics of wines after one month. Among others, ellagitannins confirmed their potentialities in added wine regarding increased antioxidant capacity and polymeric pigments ratio. Nevertheless, astringency and bitterness are affected in different extent by the matrix, highlighting the influence of wine features on the final product sensory properties

DOI:

Publication date: September 7, 2021

Issue: Macrowine 2021

Type: Article

Authors

Luca Rolle

University of Turin – Department of Agricultural, Forest and Food Sciences,Maria Alessandra PAISSONI, University of Turin, Italy Giovanni BITELLI, University of Turin, Italy Mar VILANOVA, CSIC- Misión Biológica de Galicia, Spain Carlo MONTANINI, AEB S.p.A., Italy Simone GIACOSA, Università degli Studi di Torino, Italy Luca ROLLE, University of Turin, Italy Susana RÍO SEGADE, University of Turin, Italy

Contact the author

Keywords

oenological tannins, phenolic compounds, antioxidant capacity, astringency, descriptive analysis

Citation

The future of wine grape growing regions in europe

Recent warming trends in climatic patterns are now evident from observational studies. Nowadays, investigating the possible impacts of climate change on biological systems has a great importance in several fields of science.

Comportamiento de la variedade “Touriga Nacional” en la Región Demarcada del Douro, en diferentes condiciones climáticas y edáficas

A Região Demarcada do Douro, oferece uma diversidade geográfica, climática e biológica (grande número de castas em cultivo) extremamente grande e complexa, originando vinhas

Méthodologie pour application et valorisation des études de terroir dans les caves cooperatives des Côtes du Rhône (France)

L’appellation d’origine contrôlée “Côtes du Rhône” se caractérise par une très forte implantation du mouvement coopératif. Afin de mieux exploiter le potentiel qualitatif de leurs terroirs, plusieurs coopératives élaborent des “cuvées terroir”, résultat des sélections de vendanges provenant de différents secteurs.

Effects of a new vacuum evaporation method on chemical and sensory properties of must and wine

A new process for vacuum evaporation was developed where evaporation takes place near the inner surface of a vortex produced by a rotor submerged in the liquid. Contrary to the state of the art the Vortex rotor process does not need a vacuum vessel but the rotating liquid creates a geometrically stable low pressure void surrounded by a vortex stabilized by the equilibrium between centrifugal forces and the pressure difference. First tests with water and sugar solutions at concentrations similar to grape must were conducted to verify the theoretical predictions, test the performance under different conditions and study the effect of various process parameters (Rösti et al 2015).

Directed Evolution of Oenococcus oeni: optimising yeast-bacteria interactions for improved malolactic fermentation

Malolactic fermentation (MLF) is a secondary step in the vinification process and it follows alcoholic fermentation (AF) which is predominantly carried out by Saccharomyces cerevisiae. These two processes result in the degradation of metabolites to produce secondary metabolites which also contribute to the final wine flavour and quality. AF results in the production of ethanol and carbon dioxide from sugars and MLF stems from the degradation of L-malic acid (a dicarboxylic acid) to L-lactic acid (a monocarboxylic acid). The latter process results in a smoother texture as the acidity of the wine is reduced by the process, it also adds to the flavour complexity of the wine.