WAC 2022 banner
IVES 9 IVES Conference Series 9 WAC 9 WAC 2022 9 3 - WAC - Posters 9 Eugenol:  a new marker of hybrid vines? The case study of Baco Blanc in Armagnac

Eugenol:  a new marker of hybrid vines? The case study of Baco Blanc in Armagnac

Abstract

Nowadays, winemaking is dealing with great challenges, notably climate change, disease resistance and low pesticide inputs, desire for more sustainable agricultural productions and permanent changing of consumer preference. Trying to propose practice improvements, scientists are exploring vine hybridization a paradoxically old but still actual way to take up such challenges (Pedneault & Provost, 2016). Phylloxera crisis in Europe (XIXth century) was a crucial step for improving hybridization in grapevine. Unfortunately some of the wines produced then presented redibitory sensorial default and were finally excluded for getting the PDO (Protected Designation of Origin) wine label in France.

 However, one grape variety from Armagnac vineyard resisted despite the ban: the Baco blanc, a complex hybrid of Vitis labrusca x Vitis riparia x Vitis vinifera. Baco was created to be a disease tolerant vine and productive vine of white wine intended for distillation (Baco, 1925).

Armagnac white brandies elaborated with only Baco Blanc present an atypical chemical profile. Eugenol, a phenylpropenic compound, usually known to be released by contact with oak, is significantly more concentrated in white brandies made with Baco than same products made with V.vinifera cultivars. Moreover, eugenol has been identified in other hybrid vines (Sun et al., 2011). Pure form of eugenol has a clove aroma and a noticeable and well-known antiseptic action, a gustative impact including an anesthesic power. These observations raises plenty of questions but the main ones are: “Is there a link between tolerance of the Baco to diseases and the presence of eugenol?”; “What is the dynamic of eugenol levels during spirit making?”; “Is there a link between the eugenol presence and the typicity of Baco?”.

Thus, we quantified eugenol in plants, grapes, musts, wines and distillates by HS-SPME-GC/MS. In grapes, a greater eugenol concentration and accumulation during maturation occurred in Baco Blanc than in other V.vinifera cultivars we tested (Ugni Blanc and Folle Blanche). In Baco Blanc wines, the use of enzymes increases the eugenol content during first steps of winemaking and highlights the existence of both eugenol forms, bounded and free fractions. Furthermore, eugenol amounts seemed to increase along with the storage duration on lees (before distillation). Finally, alambic characteristics may influence the alcohol content which may also impact eugenol concentration.

DOI:

Publication date: June 27, 2022

Issue: WAC 2022

Type: Article

Authors

Xavier Hastoy, Céline Franc, Laurent Riquier, Stéphanie Marchand-Marion, Marie-Claude Ségur, Marc Fermaud, Gilles De Revel

Presenting author

Xavier Hastoy – Université Bordeaux, Unité de recherche Œnologie, EA 4577, USC 1366 INRAE, ISVV, 33882 Villenave d’Ornon cedex, France

Université Bordeaux, Unité de recherche Œnologie, EA 4577, USC 1366 INRAE, ISVV, 33882 Villenave d’Ornon cedex, France | Université Bordeaux, Unité de recherche Œnologie, EA 4577, USC 1366 INRAE, ISVV, 33882 Villenave d’Ornon cedex, France | Université Bordeaux, Unité de recherche Œnologie, EA 4577, USC 1366 INRAE, ISVV, 33882 Villenave d’Ornon cedex, France | Bureau National Interprofessionnel de l’Armagnac (BNIA), 32800 Eauze, France | INRAE, UMR SAVE, Bordeaux Science Agro, ISVV, F-33882, Villenave d’Ornon, France | Université Bordeaux, Unité de recherche Œnologie, EA 4577, USC 1366 INRAE, ISVV, 33882 Villenave d’Ornon cedex, France

Contact the author

Keywords

Eugenol-Baco blanc-Brandies-Armagnac-Hybrid vines

Tags

IVES Conference Series | WAC 2022

Citation

Related articles…

Modeling the suitability of Pinot Noir in Oregon’s Willamette Valley in a changing climate

Air temperature is the key driver of grapevine phenology and a significant environmental factor impacting yield and quality for a winegrape growing region. In this study the optimal downscaled CMIP5 ensemble for computing thegrowing season average temperature (GST) viticulture climate classification index was determined to spatially compute on a decadal basis predictions of the GST climate index and the grapevine sugar ripeness (GSR) model for Pinot Noir throughout the Willamette Valley (WV) American Viticultural Area (AVA). Forecasts for average temperature and a 220 g/L target sugar concentration level were computed using daily Localized Constructed Analogs (LOCA) downscaled CMIP5 historic and Representative Concentration Pathways (RCP) future climate projections of minimum and maximum daily temperature. We explore spatiotemporal trends of the GST climate classification index and Pinot Noir specific applications of the GSR phenology model for the WV AVA. Spatiotemporal computations of the GST climate index and Pinot Noir specific applications of the GSR model enable the opportunity to explore relationships between their computed values with one intent being to provide updated GST ranges that better align with current temperature-based modeling understanding of Pinot Noir grapevine phenology and the viticultural application of LOCA CMIP5 climate projections for the WV AVA. The Pinot Noir specific applications of the GSR model or the GST index with updated bounds indicate that the percent of the WV AVA area suitable for Pinot Noir production is currently at or near its peak value in the upper 80s to lower 90s of this century.

Revealing the Barossa zone sub-divisions through sensory and chemical analysis of Shiraz wine

The Barossa zone is arguably one of the most well-recognised wine producing regions in Australia and internationally; known mainly for the production of its distinct Shiraz wines. However, within the broad Barossa geographical delimitation, a variation in terroir can be perceived and is expressed as sensorial and chemical profile differences between wines. This study aimed to explore the sub-division classification across the Barossa region using chemical and sensory measurements. Shiraz grapes from 4 different vintages and different vineyards across the Barossa (2018, n = 69; 2019, n = 72; 2020, n = 79; 2021, n = 64) were harvested and made using a standardised small lot winemaking procedure. The analysis involved a sensory descriptive analysis with a highly trained panel and chemical measurement including basic chemistry (e.g. pH, TA, alcohol content, total SO2), phenolic composition, volatile compounds, metals, proline, and polysaccharides. The datasets were combined and analysed through an unsupervised, clustering analysis. Firstly, each vintage was considered separately to investigate any vintage to vintage variation. The datasets were then combined and analysed as a whole. The number of sub-divisions based on the measurements were identified and characterised with their sensory and chemical profile and some consistencies were seen between the vintages. Preliminary analysis of the sensory results showed that in most vintages, two major groups could be identified characterised with one group showing a fruit-forward profile and another displaying savoury and cooked vegetables characters. The exploration of distinct profiles arising from the Barossa wine producing region will provide producers with valuable information about the regional potential of their wine assisting with tools to increase their target market and reputation. This study will also provide a robust and comprehensive basis to determine the distinctive terroir characteristics which exist within the Barossa wine producing region.

Biodiversity in the vineyard agroecosystem: exploring systemic approaches

Biodiversity conservation and restoration are essential for guarantee the provision of ecosystem services associated to vineyard agroecosystem such as climate regulation trough carbon sequestration and control of pests and diseases. Most of published research dealing with the complexity of the vineyard agroecosystems emphasizes the necessity of innovative approaches, including the integration of information at different temporal and spatial scales and development of systemic analysis based on modelling. A biodiversity survey was conducted in the Franciacorta wine-growing area (Lombardy, Italy), one of the most important Italian wine-growing regions for sparkling wine production, considering a portion of the territory of 112 ha. The area was divided into several Environmental Units (EUs), defined as a whole vineyard or portion of vineyard homogenous in terms of four agronomic characteristics: planting year, planting density, cultivar, and training system. In each EU a set of compartments was identified and characterised by specific variables. The compartments are meteorology, morphology (altitude, slope, aspect, row orientation, and solar irradiance), ecological infrastructures and management. The landscape surrounding EU was also characterised in terms of land-use in a buffer zone of 500 m. For each component a specific methodology was identified and applied. Different statistical approaches were used to evaluate the method to integrate the information related to different compartments within the EU and related to the buffer zone. These approaches were also preliminarily evaluated for their ability to describe the contribution of biodiversity and landscape components to ecosystem services. This methodological exploration provides useful indication for the development of a fully systemic approach to structural and functional biodiversity in vineyard agroecosystems, contributing to promote a multifunctional perspective for the all wine-growing sector.

Vineyards and clay minerals: multi-technique analytical approach and correlations with soil properties

Purpose of this research is to quantitatively assess the mineral component of vineyard soils, with particular attention to the mineralogical analysis of clays, which represent an element of high importance in the vineyard culture as well as in general agriculture. An X-ray diffraction (XRD) / thermogravimetric (TG) multi-technique analytical approach was developed, tested on soil samples taken from vineyards around the world. This codified analytical procedure was necessary to obtain precise qualitative and quantitative mineralogical data, globally comparable to distinguish the geopedological identity of the vineyards. Soil samples from vineyards of various locations were analysed, in very different geological conditions. The bulk-rock quantitative phase analysis (QPA) was obtained by the Rietveld method while the detailed composition of the clay-sized fraction was determined by modelling of the oriented X-ray diffraction patterns. The research provided a precise classification of the mineral component of soils, distinguishing the mineral phases of the clays and the so-called mixed-layer clay minerals. We found that the content in mixed layers can be directly correlated with the water retention and the cation exchange capacity ​​of the soil, while the presence of other clayey minerals and phyllosilicates in this research did not affect this CEC parameter, which codes the fertility level of the soils. The study demonstrates that terroir, in particular soils formed in complex or very different geological conditions, can only be effectively interpreted by properly analysing its mineral phases, in particular the mixed-layer clay component. These are characteristic abiotic ecological indicators, which may have specific eco-physiological influences on the plant.

Climate change projections to support the transition to climate-smart viticulture

The Earth’s system is undergoing major changes through a wide range of spatial and temporal scales as a response to growing anthropogenic radiative forcing, which is pushing the whole system far beyond its natural variability. Sources of greenhouse gases largely exceed their sinks, thus leading to a strengthened greenhouse effect. More energy is thereby being supplied to the system, with inevitable shifts in climatic patterns and weather regimes. Over the last decades, these modifications have been manifested in the full statistical distributions of the atmospheric variables, with dramatic changes in the frequency and intensity of extremes. Natural hazards, such as severe droughts, floods, forest fires, or heatwaves, are being triggered by extreme atmospheric events worldwide, thus threatening human activities. Viticultculture is not only exposed to changing climates but is also highly vulnerable, as grapevine phenology and physiological development are strongly controlled by atmospheric conditions. Therefore, the assessment of climate change projections for a given region is critical for climate change adaptation and risk reduction in viticulture. By adopting timely and suitable measures, the future sustainability and resiliency of the sector can be fostered. Climate-grapevine chain modelling is an essential tool for better planning and management. However, the accuracy of the resulting projections is limited by many uncertainties that must be duly taken into account when transferring knowledge to stakeholders and decision-makers. Climate-smart viticulture will comprise ensembles of locally tuned strategies, envisioning both adaptation and mitigation, assisted by emerging technologies and decision-support systems.