 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

Impact of aspects of the polysaccharide structure of mannoproteins on their interactions with Enological Tannins

Mannoproteins (MPs) with different structure of their polysaccharide part (branching, substitutions, …) were used to better understand the impact of characteristics of the usual structure of MPs when interacting with Grape Seed Tannins (ST).

Drought tolerance assessment and differentiation of grapevine cultivars using physiological metrics: insights from field studies

This study aimed to validate a protocol and compare metrics for evaluating drought tolerance in two Vitis vinifera grapevine cultivars under field conditions. Various metrics were calculated to represent the physiological responses of plants to progressive water deficit. Data were collected from Sauvignon Blanc and Chardonnay plants subjected to three irrigation levels during the 2022-2023 season, along with data from three previous seasons. Hydro-escape areas were used to assess the plant’s ability to reduce water potential with decreasing soil water availability.

Effect of redox mediators on the activity of laccase from Botrytis cinerea against volatile phenols

Volatile phenols namely 4-ethylphenol and 4-ethylguaiacol are formed by enzymatic decarboxylation of hydroxycinnamic acids by Brettanomyces yeasts to give vinylphenols and subsequent reduction of the vinyl group to form the correspondent ethylphenols. The presence of these compounds in wine affects negatively its aromatic quality, conferring unpleasant animal and phenolic odor when present in quantities above the olfactory detection threshold [1]. Several methods have been described to remove these undesirable compounds from wines, including the use laccase enzymes [2, 3]. Due to this, the aim of this work was to evaluate the effect of several natural redox mediators on the activity of Botrytis cinerea laccase against these volatile phenols.

Sustainability as system innovation: sustainability as system innovation: a returnable system for glass wine bottles

Introduction increasing sustainability is essential and a societal challenge, requiring fundamental changes in behaviour and attitudes. This applies to both producers and consumers. For the wine industry in particular, such a change is a major challenge. An eip-agri research project is evaluating the introduction of a returnable glass system in the german wine industry as a key solution for increasing sustainability. Given the need for change associated with a returnable system, the project is theoretically grounded in systems innovation, as this approach provides solutions for complex, transformative change.

“Gheo” per la vitivinicoltura: un progetto per la produzione dl vini dl alta qualità

Il settore primario, ed in particolare quello agricolo, sta attraversando un periodo particolarmente delicato. Sia gli aspetti della produzione che quelli della commercializzazione vengono infatti messi in discussione da nuovi indirizzi economici e tecnologici.