Macrowine 2021
IVES 9 IVES Conference Series 9 Update knowledge about the presence of condensed tannins in grapes and their contributions to astringency perception

Update knowledge about the presence of condensed tannins in grapes and their contributions to astringency perception

Abstract

Condensed tannin is a principle group of polyphenol compounds derived from grape, greatly contributing to the bioactivity and the sensory perception of wine. Condensed tannins present as a heterogeneous mixture in nature involving various degrees of both polymerization and galloylation. Even though multiple attempts focusing on fractionation of grape condensed tannins by solid-phase have been conducted over the past decades, few individual tannins have been purified and identified. Hence, our knowledge on grape and wine condensed tannin moleculars has to be limited at the several known monomeric, dimeric and trimeric proanthocyanidins. In the present study, a rapid and effective approach was developed to isolate the galloylated proanthocyanidin from the non-galloylated forms in grape seed tannins and fractionate the non-galloylated proanthocyanidin according to their degree of polymerization by the technique of Centrifugal partition chromatography (CPC). The application of CPC on grape tannins fractionation is efficient, less-time consuming, less expensive and with higher recovery. More importantly, it could effectively isolate galloylated tannins at the beginning and eliminate its interference in the other fractions. After fractionation performed by the technique of CPC, the repurification was achieved by either preparative hydrophilic interaction chromatography or reversed phase high-performance liquid chromatography (HPLC). Eventually, a series of individual condensed tannins with certain degree of polymerization and galloylation from grape were isolated successively. Analyte identity and purity were examined by reversed-phase UPLC-DAD-ESI-Q-TOF and normal-phase HPLC-UV-Fluo-MS, respectively. The astringency perception contributions of the purified individual tannins were examined by the approach of salivary binding ability test. The results were observed by HPLC-Fluo and quantified by the difference of the amount of proanthocyanidins between before and after interaction.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Wen Ma*, Hua Li, Michael Jourdes, Pierre Waffo-Téguo, Pierre-Louis Teissedre

*ISVV

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

Related articles…

Characterization of non-Saccharomyces yeast and its interaction with Saccharomyces cerevisiae with investigation of fermentation kinetics and aromatic composition

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.20.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Comparison of fortified, sfursat and passito winemaking techniques for the enhancement of the oenological potential of the black grape cultivar Moscato nero d’Acqui (Vitis vinifera L.)

One of the key factors of the economical development of viticulture and wine industry in specific limited areas is the exploitation of ancient, local grape varieties. Therefore, in recent years the growing interest to rediscover minor varieties, previously cultivated, has promoted many studies. With this regard, the focus of this study was the Vitis vinifera L. cultivar Moscato nero d’Acqui, nowadays found only in old vineyards in the Acqui zone (North-West Italy). In particular, the aims of this work were: i) to investigate secondary metabolites profile of the grapes, and ii) to evaluate the attitude to the production of special wines.

Wood from barrique: release of phenolic compounds and permeability to oxygen

Chemical and sensory changes occurring in red wine during ageing in oak barrique are due to the slow and gradual entrance of oxygen along with a release of ellagic tannin from the wood. Though oxygen can enter the cask through the bunghole, it is not clear the role of permeation through the wood staves as well as the amount of oxygen entering by permeation. The distribution of the released ellagic tannins in the wine ageing is also unknown. The oxygen passing through the bunghole may have a different wine ageing effect compared to the oxygen permeating through the wooden staves owing to the uneven ellagic tannin concentration throughout the wine.

Quantification of the production of hydrogen peroxide H2O2 during wine oxidation

Chemical studies aiming at assessing how a wine reacts towards oxidation usually focus on the characterization of wine constituents, such as polyphenols, or oxidation products. As an alternative, the key oxidation intermediate hydrogen peroxide H2O2 has never been quantified, although it plays a pivotal role in wine oxidation. H2O2 is obtained from molecular oxygen as the result of a first cascade of oxidation reactions involving metal ions and polyphenols. The produced H2O2 then reacts in a second cascade of oxidation to produce reactive hydroxyl radicals that can attack almost any chemical substrate in wine.

Characterization of commercial enological tannins and its effect on human saliva diffusion

Commercial oenological tannins (TECs) are widely used in the wine industry. TECs are rich in condensed tannins, hydrolyzable tannins or a mixture of both. Wine grapes are a important source of proanthocyanidins or condensed tannins while oak wood possess a high concentration of hydrolyzable tannins (Obreque-Slier et al., 2009). TECs contribute with the antioxidant capacity of wine, catalyze oxide-reduction reactions and participate in the removal of sulfur compounds and metals.