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…

Bioclimatic shifts and land use options for Viticulture in Portugal

Land use, plays a relevant role in the climatic system. It endows means for agriculture practices thus contributing to the food supply. Since climate and land are closely intertwined through multiple interface processes, climate change may lead to significant impacts in land use. In this study, 1-km observational gridded datasets are used to assess changes in the Köppen–Geiger and Worldwide Bioclimatic (WBCS)

austrianvineyards.com: online viewer of all designations of Austrian wine

To digitally record and present all the origins of Austrian wines in the same perfect and clear way was the motivation for the Austrian Wine Marketing Board (Austrian Wine) to start with the project in 2018. In June 2021 the results were presented to the public in an online viewer showing all the designations of Austrian wine, available at https://austrianvineyards.com in a largely barrier-free manner. The online viewer provides tailored individual maps fitted to the respective zoom level. The smallest unit of wine-origins in Austria is called Ried and is displayed in a plot-specific manner highlighting areas under vine. Information on the Ried include administrative district, winegrowing municipality, cadastral municipality, large collective vineyard site, specific winegrowing region, generic winegrowing region, winegrowing area and, in many cases, an illustrative picture. Complementary data on the size, elevation (minimum-maximum), orientation (in 8 sectors plus flat) and gradient (minimum, maximum, average) are based on the area under vine according to the EU’s Integrated Administration and Control System. Additional information covers climate data. The diagrams are taken from the monthly breakdown of data in the annals of the Central Institute for Meteorology and Geodynamics, Austria provide a display of values for air temperature, precipitation, and sunshine hours for the reference year and the long-term average. Seasonal aggregated data on temperature, precipitation, and sunshine hours complete the display. Short descriptions with emphasis on geology and soil, field name in historical maps, etymology of the denomination, and main planted variety complements the available information for the main designations in the online viewer. These descriptions are compiled by winegrowers, geologists, historians, and journalists. All the information and data can be extracted to a pdf-file. Printed vineyard maps are also available. Missing content regarding wine origins in Styria will be completed in winter 2021/22.

Variations of soil attributes in vineyards influence their reflectance spectra

Knowledge on the reflectance spectrum of soil is potentially useful since it carries information on soil chemical composition that can be used to the planning of agricultural practices. If compared with analytical methods such as conventional chemical analysis, reflectance measurement provides non-destructive, economic, near real-time data. This paper reports results from reflectance measurements performed by spectroradiometry on soils from two vineyards in south Brazil. The vineyards are close to each other, are on different geological formations, but were subjected to the same management. The objective was to detect spectral differences between the two areas, correlating these differences to variations in their chemical composition, to assess the technique’s potential to predict soil attributes from reflectance data.To that end, soil samples were collected from ten selected vine parcels. Chemical analysis yield data on concentration of twenty-one soil attributes, and spectroradiometry was performed on samples. Chemical differences significant to a 95% confidence level between the two studied areas were found for six soil attributes, and the average reflectance spectra were separated by this same level along most of the observed spectral domain. Correlations between soil reflectance and concentrations of soil attributes were looked for, and for ten soil traits it was possible to define wavelength domains were reflectance and concentrations are correlated to confidence levels from 95% to 99%. Partial Least Squares Regression (PLSR) analyses were performed comparing measured and predicted concentrations, and for fifteen out of 21 soil traits we found Pearson correlation coefficients r > 0.8. These preliminary results, which have to be validated, suggest that variations of concentration in the investigated soil attributes induce differences in reflectance that can be detected by spectroradiometry. Applications of these observations include the assessment of the chemical content of soils by spectroradiometry as a fast, low-cost alternative to chemical analytical methods.

Effect of one-year cover crop and arbuscular mycorrhiza inocululation in the microbial soil community of a vineyard

The microbial composition of the soil is an important factor to consider in viticulture, since its influence on the “terroir” and on the organoleptic properties of the wine have been demonstrated. Different agronomic techniques have the potential to modify the composition and functionality of the soil microbial community. Maintaining green covers is known to increase soil microbial diversity. The direct application of inoculum of beneficial microorganisms to the soil has also been used to increase their abundance. However, the environmental conditions of each site seem to have a determining weight in the result of these practices. In this study, we compared the effect on the microbial community of a cover crop with legumes in autumn and the inoculation of grapevines with commercial inoculum bases on Rhizophagus irregularis and Funeliformis mosseae in the previous spring. The study has been carried out in a vineyard in Binissalem, Mallorca, Spain. After applying the treatments, we will analyze the soil microbial communities using the data obtained from Illumina amplification of soil DNA from the 16S and ITS regions to analyze bacteria and fungi community, respectively. In addition, we will record the physicochemical characteristics of the soil at each sampling point. The result showed that agronomic management, in the short term, has less influence than soil characteristics on the composition of the soil microbiome. With these results, we can conclude that in a vineyard, agricultural techniques should focus on improving the characteristics of the soil to improve the biodiversity of the soil microbiota.

Variety and climatic effects on quality scores in the Western US winegrowing regions

Wine quality is strongly linked to climate. Quality scores are often driven by climate variation across different winegrowing regions and years, but also influenced by other aspects of terroir, including variety. While recent work has looked at the relationship between quality scores and climate across many European regions, less work has examined New World winegrowing regions. Here we used scores from three major rating systems (Wine Advocate, Wine Enthusiast and Wine Spectator) combined with daily climate and phenology data to understand what drives variation across wine quality scores in major regions of the Western US, including regions in California, Oregon and Washington. We examined effects of variety, region, and in what phenological period climate was most predictive of quality. As in other studies, we found climate, based mainly on growing degree day (GDD) models, was generally associated with quality—with higher GDD associated with higher scores—but variety and region also had strong effects. Effects of region were generally stronger than variety. Certain varieties received the highest scores in only some areas, while other varieties (e.g., Merlot) generally scored lower across regions. Across phenological stages, GDD during budbreak was often most strongly associated with quality. Our results support other studies that warmer periods generally drive high quality wines, but highlight how much region and variety drive variation in scores outside of climate.