terclim by ICS banner
IVES 9 IVES Conference Series 9 THE FLAVANOL PROFILE OF SKIN, SEED, WINES, AND POMACE ARE CHARACTERISTIC OF EACH TYPOLOGY AND CONTRIBUTES TO UNDERSTAND THE FLAVAN- 3-OLS EXTRACTION DURING RED WINEMAKING

THE FLAVANOL PROFILE OF SKIN, SEED, WINES, AND POMACE ARE CHARACTERISTIC OF EACH TYPOLOGY AND CONTRIBUTES TO UNDERSTAND THE FLAVAN- 3-OLS EXTRACTION DURING RED WINEMAKING

Abstract

Wine flavanols are extracted from grape skin and seeds along red winemaking. Potentially, eight flavan-3-ol subunits may be present as monomers or as tannins constituents, being these catechin, epicathechin, gallocatechin, epigallocatechin end the gallates of the mentioned units. In this work the flavanol profiles of grape skins and seeds before (grapes) and after (pomace) red winemaking were studied together with the one in the corresponding wines. The trials were made over two vintages in Vitis vinifera cv. Tannat, Syrah and Marselan from Uruguay. A total of twenty wines were made under the same experimental conditions. The flavanol fractions were isolated from the samples using C18 solid phase extraction cartridges. A LC-MS system was used for analysis, composed by an HPLC couples to a mass spectroscopy system (triple-quadrupole ESI-MS/MS). Catechin and epicatechin registered the higher relative abundance in all typologies as expected. In the skins, the percentage of catechin was significantly higher than that of epicatechin while the opposite was observed in the seeds. In agreement with literature, the relative proportion of gallates was much higher in the seed than in the skins, while pro-dephinidins (PD%) exceeded 10% in skins and were found at traces levels in seeds. There were no differences among cultivars in the skins flavanol profile, but in the seeds, Marselan had a characteristic high proportion of catechin that almost matched that of epicatechin. Moreover, Tannat had higher proportion of epicatechin-gallate than catechin-gallate, while the opposite was registered in Syrah and Marselan. The seed-pomace flavan-3-ol monomers profile matched that of the seeds in the three-cultivar studied, showing that all compounds were extracted at the same rate along maceration. Nevertheless, the skin-pomace had a much higher proportion of epicatechin and of gallates that observed in skins, and a much lower of PD. These differences were of higher magnitude in the flavan-3-ol monomers profile, and in Marselan, which wines had a much higher contribution of flavanols from the seeds (observed as low PD% and high of gallates and epicatechin) than Tannat and Syrah. In Syrah and Tannat wines, the PD% was just slightly lower than in skins, while in Marselan they were much lower. Thus, skins adsorb fla-vanols released from seeds during maceration, while the trihydroxylated prodelphinidin monomers are the more easily extracted flavanols from skins.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Sergio Gómez-Alonso², José Pérez-Navarro², Esteban García-Romero³, Adela Mena-Morales³, Diego Piccardo¹, Gustavo Gon-zález-Neves¹

1. Facultad de Agronomía (Universidad de la República). Avda. Garzón 780. C.P., 12900 Montevideo, Uruguay 
2. Instituto Regional de Investigación Científica Aplicada (IRICA), University of Castilla-La Mancha, Av. Camilo José Cela s/n, 13071 Ciudad Real, Spain 
3. Instituto Regional de Investigación y Desarrollo Agroalimentario y Forestal de Castilla-La Mancha (IVICAM-IRIAF), Ctra. Albacete s/n, 13700 Tomelloso, Spain

Contact the author*

Keywords

Tannins, Flavanols, Winemaking, Extraction

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

UNTARGETED METABOLOMICS ANALYSES TO IDENTIFY A NEW SWEET COMPOUND RELEASED DURING POST-FERMENTATION MACERATION OF WINE

The gustatory balance of dry wines is centered on three flavors, sourness, bitterness and sweetness. Even if certain compounds were already identified as contributing to sweetness, some taste modifications remain largely unexplained1,2. Some empirical observations combined with sensory analyzes have shown that an increase of wine sweetness occurs during post-fermentation maceration³. This step is a key stage of red winemaking during which the juice is left in contact with the marc, that contains the solid parts of the grape (seeds, skins and sometimes stems). This work aimed to identify a new taste-active compound that contributes to this gain of sweetness.

Read More

IMPACT OF MANNOPROTEIN N-GLYCOSYL PHOSPHORYLATION AND BRANCHING ON WINE POLYPHENOL INTERACTIONS WITH YEAST CELL WALLS

Yeast cell walls (CWs) may adsorb wine components with a significant impact on wine quality. When dealing with red wines, this adsorption is mainly related to physicochemical interactions between wine polyphenols and cell wall mannoproteins. However, mannoproteins are a heterogeneous family of complex peptidoglycans including long and highly branched N-linked oligosaccharides and short linear O-linked oligosaccharides, resulting in a huge structural diversity.

Read More

Metabolomics for grape and wine research: exploring the contributions of amino acids to wine flavour

A critical aspect of wine quality is the overall expression of wine flavour, which is formed by the interplay of volatile aroma compounds, their precursors, and taste and matrix components.
Grapes directly contribute to wine only a small number of potent aroma compounds, and the unique
sensory attributes and perceived quality of a wine result from combining 100s of metabolites of grapes, yeast and bacteria, and oak wood.

Read More

CONTRIBUTION OF VOLATILE THIOLS TO THE AROMA OF RIESLING WINES FROM THREE REGIONS IN GERMANY AND FRANCE (RHEINGAU, MOSEL, AND ALSACE)

Riesling wines are appreciated for their diverse aromas, ranging from the fruity fresh characters in young vintages to the fragrant empyreumatic notes developed with aging. Wine tasters often refer to Riesling wines as prime examples showcasing terroir, with their typical aroma profiles reflecting the geographical provenance of the wine. However, the molecular basis of the distinctive aromas of these varietal wines from major Riesling producing regions in Europe have not been fully elucidated. In this study, new lights were shed on the chemical characterization and the sensory contribution of volatile thiols to Riesling wines from Rheingau, Mosel, and Alsace. First, Riesling wines (n = 46) from the three regions were collected and assessed for their aroma typicality by an expert panel.

Read More

WINE RACKING IN THE WINERY AND THE USE OF INERT GASES: CONTROL AND OPTIMIZATION OF THE PROCESS

Atmospheric oxygen (O₂) generates oxidation in wines that affect their physicochemical and sensory evolution. The O₂ uptake in the different winemaking processes is generally considered to be negative for the sensory characteristics of white and rosé wines. Wine racking is a critical point of O₂ uptake, as the large surface area of the wine exposed during this operation and the inability to maintain an effective inert gas blanket over it.
The aim was to study the uptake of O₂ during the racking of a model wine as a reference and to compare with purging the destination tank with different inert gases.

Read More