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…

Influence of agrophotovoltaic on vine and must in a cool climate

The current energy crisis means that interest in agrophotovoltaics has increased significantly. The reason behind this is that the system aims to combine agricultural production with energy production. During the three-year period from 2020 to 2022, the effects of photovoltaic panels on the vine, the yield and the quality of the must were studied in Walenstadt in northern Switzerland, an area with a cool, humid climate. 65 Pinot noir vines were planted in the 160m2 study area. Because of the large edge effects, only 3 repetitions with 4 vines each could be created. A significantly lower leaf infestation by Plasmopara viticola was observed among the panels in each of the three years.

MONITOR SOME KEY PARAMETERS THROUGH THE IMPLEMENTATION OFCONTINUOUS CONTROL SYSTEMS OF THE MUST-WINE DURING MACERATION-FERMENTATION IN RED WINEMAKING TO MANAGE OPERATIONS IN “AUTOMATION”

This study is aimed to develop a complete tool for the winemaker with, complete and targeted “winemaking recipes” that can be adapted to criteria set by the winemaker, such as: grape variety, grape health status, degree of ripening, desired wine, redox status throughout the alcoholic fermentation.
To get such aim, specific sets of experiments using red grape juices from different varieties (Nebbiolo, Barbera, Pinot noir, etc.) collected at different technological and phenolic maturity points, will be held with “automatized 4.0 tanks” equipped with sensors for measuring: redox potential, dissolved oxygen, relative density, temperature, and color in order to collect a sufficient amount of data preparatory to the creation of operating models in the most widely winemaking situations in which the automatized 4.0 tanks “will be able to independently respond” with the right corrective actions (opening/closing aeration valve, execution/block pumping overs , etc.) if the key parameters exceed the limits of the recommended ranges set in the selected recipe.

Microbial ecosystems in wineries – molecular interactions between species and modelling of population dynamics

Microbial ecosystems are primary drivers of viticultural, oenological and other cellar-related processes
such as wastewater treatment. Metagenomic datasets have broadly mapped the vast microbial species
diversity of many of the relevant ecological niches within the broader wine environment, from vineyard
soils to plants and grapes to fermentation. The data highlight that species identities and diversity
significantly impact agronomic performance of vineyards as well as wine quality, but the complexity
of these systems and of microbial growth dynamics has defeated attempts to offer actionable
tools to guide or predict specific outcomes of ecosystem-based interventions.

ALCOHOLIC FERMENTATION AND COLOR OF ROSÉ WINES: INVESTIGATIONS ON THE MECHANISMS RESPONSIBLE FOR SUCH DIVERSITY

Color is one of the key elements for the marketing of rosé wines due to their packaging in transparent bottles. Their broad color range is due to the presence of pigments belonging to phenolic compounds extracted from grapes or formed during the wine-making process. However, the mechanisms responsible for such diversity are poorly understood. The few investigations performed on rosé wines showed that their phenolic composition is highly variable, close to that of red wines for the darkest rosés but very different for light ones [1]. Moreover, large variations in the extent of color loss taking place during fermentation have been reported but the mechanisms involved and causes of such variability are unknown.

PHOTOCHEMICAL DEGRADATION OF TRYPTOPHAN IN MODEL WINE: IMPACT OF HEAVY METALS AND OXYGEN ON 2-AMINOACETOPHENONE FORMATION

The wine industry worldwide faces more and more challenges due to climate change, such as increased dryness in some areas, water stress, sunburn and early harvesting during hot summer temperatures¹. One of the resulting problems for the wine quality might be a higher prevalence of the untypical aging off-flavor (ATA)². A substance, which Rapp and Versini made responsible for ATA, is the 2-aminoace-tophenone (2-AAP)³. 2-AAP in wine causes a naphthalene, wet towels, wet wool, acacia flower or just a soapy note⁴.