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…

RED WINE AGING WITHOUT SO₂: WHAT IMPACT ON MICROBIAL COMMUNITY?

Nowadays, the use of food preservatives is controversial, SO2 being no exception. Microbial communities have been particularly studied during the prefermentary and fermentation stages in a context of without added SO2. However, microbial risks associated with SO2 reduction or absence, particularly during the wine aging process, have so far been little studied. The microbiological control of wine aging is a key issue for winemakers wishing to produce wines without added SO2. The aim of the present study is to evaluate the impact of different wine aging strategies according to the addition or not of SO2 on the microbiological population levels and diversity.

FLAVONOID POTENTIAL OF MINORITY RED GRAPE VARIETIES

The alteration in the rainfall pattern and the increase in the temperatures associated to global climate change are already affecting wine production in many viticultural regions all around the world (1). In fact, grapes are nowadays ripening earlier from a technological point of view than in the past, but they are not necessarily mature from a phenolic point of view. Consequently, the wines made from these grapes can be unbalanced or show high alcohol content. Dramatic shifts in viticultural areas are currently being projected for the future (2).

ESTIMATING THE INITIAL OXYGEN RELEASE (IOR) OF CORK CLOSURES

Many factors influence aging of bottled wine, oxygen transfer through the closure is included. The maximum uptake of wine before oxidation begins varies from 60 mg.L-¹ to 180 mg.L-1 for white and red wines respectively [1].
The process of bottling may lead to considerable amounts of oxygen. The actual contribution of the transfer through the closure system becomes relevant at the bottle storage, but the amounts are small compared to prepacking operations [2] and to the total oxygen attained during filling.

INFLUENCE OF GRAPE RIPENESS ON MACROMOLECULES EXTRACTABILITY FROM GRAPE SKIN TISSUES AND GRAPE SEEDS DURING WINEMAKING

A consequence of climate change is the modification of grape harvest quality and physico-chemical parameters of the obtained wine: increase in alcoholic degree, decrease in pH, and modification of the extractability of macromolecules, which leads to problems of microbiological, tartaric, colour and colloidal stability. In order to respond to these problems, the winemaking processes must be anticipated and adapted with a better knowledge of macromolecule extractability in grapes and their evolution, according to the grape variety, vintage and winemaking process. The purpose of this study was to understand 1) how the harvest date can influence the extractability of macromolecules, polysaccharides and phenolic compounds, which are responsible for wine stability 2) how to adapt the winemaking process to the harvest date in order to optimise wine quality.

INFLUENCE OF THE NITROGEN / LIPIDS RATIO OF MUSTS ON THE REVELATION OF AROMATIC COMPOUNDS IN SAUVIGNON BLANC WINE

Production of volatile compounds by yeast is known to be modulated by must nitrogen. Nevertheless, various parameter of must quality have an impact on yeast fermentation. In this study we propose to evaluate the impact of nitrogen / lipids balance on a Sauvignon Blanc grape juice (Val de Loire).
Must was prepared from the same grapes at pilot scale. Three modalities were carried out: direct pressing, direct pressing with a pre-fermentation cold stabulation and pellicular maceration before pressing.