Macrowine 2021
IVES 9 IVES Conference Series 9 Revealing the origins of old bordeaux wines using terpene quantification

Revealing the origins of old bordeaux wines using terpene quantification

Abstract

The overall quality of fine wines is linked to the development of “bouquet” during wine bottle ageing (1). Bordeaux red wine ageing bouquet is defined by the association of several odours including fresh and fruity notes sometimes related to specific compounds. Some of those molecules, such as thiols or DMS are issued from precursors produced by the grapevine (2–5). On the another hand, several compounds such as terpenes are produced by the grape as precursors (6) and released during ageing. The aroma of aged wines , the “bouquet” could originate directly in grapes thanks to flavour precursors (7). In this study we addressed the questions: What is the most important between vintage and terroir in wine identity? And is there a molecular signature in the aroma of old wines linked to grape origin and revealed during ageing?Over 80 volatile molecules including DMS, esters, terpenes, mint terpenes, C13-norisoprénoïdes, volatiles oak wood compounds and off-flavors were quantified by GC/MS in 80 red Bordeaux wines (7 domains x 12 vintages between 1990 and 2007). A statistical analysis was performed on the dataset. First, the presence of most of the targeted molecules were identified in the 80 wines and the link between their contents and the wines’ ages was evaluated. After that, the hypothesis of wine identity being linked to wood contact or off-flavors was rejected. Next, principal component analysis (PCA) on the data showed a separation between the 7 vineyards studied. Each Bordeaux area and domain could be represented by one or several molecules. Then, a discriminant factor analysis (DFA) showed the weight of each compound in the separation. The terpenes, in particular terpinen-1-ol, terpinen-4-ol and α-terpinene, were implicated to the partitioning of vineyards. A degradation of the separation of the wines is observed if terpenes levels are excluded from the data set. Nevertheless, the separation is not effective based on solely terpene levels. The profile of terpenes in the molecular signature of these Bordeaux old wines is important but the signature of studied domains is incomplete without the other compounds.These results highlight the specificity of productions areas and the existence of a molecular identity unique to each domain beyond the effect of vintage and the passage of years. The terroir and blending practiced in Bordeaux are probably involved in this singular molecular identity.

DOI:

Publication date: September 14, 2021

Issue: Macrowine 2021

Type: Article

Authors

Justine Laboyrie

Unité de recherche Oenologie, EA 4577, USC 1366 INRAE, ISVV, University of Bordeaux, Bordeaux INP, F33882 Villenave d’Ornon France ,Davide Slaghenaufi, Department of Biotechnology, University of Verona 37029 San Pietro in Cariano, Italy Giovanni Luzzini, Department of Biotechnology, University of Verona 37029 San Pietro in Cariano, Italy Maurizio Ugliano, Department of Biotechnology, University of Verona 37029 San Pietro in Cariano, Italy Laurent Riquier, Unité de recherche Oenologie, EA 4577, USC 1366 INRAE, ISVV, University of Bordeaux, Bordeaux INP, F33882 Villenave d’Ornon France Stéphanie Marchand, Unité de recherche Oenologie, EA 4577, USC 1366 INRAE, ISVV, University of Bordeaux, Bordeaux INP, F33882 Villenave d’Ornon France

Contact the author

Keywords

red wines identity, ageing, gas chromatography analysis, terpenes, terroir

Citation

Related articles…

Effect of the commercial inoculum of arbuscular mycorrhiza in the establishment of a commercial vineyard of the cultivar “Manto negro

The favorable effect of symbiosis with arbuscular mycorrhizal fungi (AMF) has been known and studied since the 60s. Nowadays, many companies took the chance to start promoting and selling commercial inoculants of AMF, in order to be used as biofertilizers and encourage sustainable biological agriculture. However, the positive effect of these commercial biofertilizers on plant growth is not always demonstrated, especially under field conditions. In this study, we used a commercial inoculum on newly planted grapevines of a local cultivar grafted on a common rootstock R110. We followed the physiological status of vines, growth and productivity and functional biodiversity of soil bacteria during the first and second years of 20 inoculated with commercial inoculum bases on Rhizophagus irregularis and Funeliformis mosseaeAMF at field planting time and 20 non-inoculated control plants. All the parameters measured showed a neutral to negative effect on plant growth and production. The inoculated plants always presented lower values of photosynthesis, growth and grape production, although in some cases the differences did not reach statistical significance. On the contrary, the inoculation supposed an increase of the bacterial functional diversity, although the differences were not statistically significant either. Several studies show that the effect of inoculation with AMF is context-dependent. The non-favorable effects are probably due to inoculation ineffectiveness under complex field conditions and/or that, under certain conditions, AMF presence may be a parasitic association. This puts into question the effectiveness of its application in the field. Therefore, it is recommended to only resort to this type of biofertilizer when the cultivation conditions require it (e.g., very low previous microbial diversity, foreseeable stress due to drought, salinity, or lack of nutrients) and not as a general fertilization practice.

Soil, vine, climate change – what is observed – what is expected

To evaluate the current and future impact of climate change on Viticulture requires an integrated view on a complex interacting system within the soil-plant-atmospheric continuum under continuous change. Aside of the globally observed increase in temperature in basically all viticulture regions for at least four decades, we observe several clear trends at the regional level in the ratio of precipitation to potential evapotranspiration. Additionally the recently published 6th assessment report of the IPCC (The physical science basis) shows case-dependent further expected shifts in climate patterns which will have substantial impacts on the way we will conduct viticulture in the decades to come.
Looking beyond climate developments, we observe rising temperatures in the upper soil layers which will have an impact on the distribution of microbial populations, the decay rate of organic matter or the storage capacity for carbon, thus affecting the emission of greenhouse gases (GHGs) and the viscosity of water in the soil-plant pathway, altering the transport of water. If the upper soil layers dry out faster due to less rainfall and/or increased evapotranspiration driven by higher temperatures, the spectral reflection properties of bare soil change and the transport of latent heat into the fruiting zone is increased putting a higher temperature load on the fruit. Interactions between micro-organisms in the rhizosphere and the grapevine root system are poorly understood but respond to environmental factors (such as increased soil temperatures) and the plant material (rootstock for instance), respectively the cultivation system (for example bio-organic versus conventional). This adds to an extremely complex system to manage in terms of increased resilience, adaptation to and even mitigation of climate change. Nevertheless, taken as a whole, effects on the individual expressions of wines with a given origin, seem highly likely to become more apparent.

Mesoclimate impact on Tannat in the Atlantic terroir of Uruguay

The study of climate is relevant as an element conditioning the typicity of a product, its quality and sustainability over the years. The grapevine development and growth and the final grape and wine composition are closely related to temperature, while climate components vary at mesoscale according to topography and/or proximity to large bodies of water. The objective of this work is to assess the mesoclimate of the Atlantic region of Uruguay and to determine the effect of topography and the ocean on temperature and consequently on Tannat grapevine behavior.

Impact of climate change on the viticultural climate of the Protected Designation of Origin “Jumilla” (SE Spain)

Protected Designation of Origin “Jumilla” (PDO Jumilla) is located in the Spanish provinces of Albacete and Murcia, in the South-eastern part of the Iberian Peninsula, where most of the models predict a severe impact of climate change in next decades. PDO Jumilla covers an area of 247,054 hectares, of which more than 22,000 hectares

Organic recycled mulches in sustainable viticulture: assessment of spontaneous plants communities and weed coverage

In recent years, developing more efficient and sustainable viticulture management has been essential due to the impact of climate change in semiarid regions. For this reason, the use of recycled organic mulching (ROM) in the vineyard has become an interesting strategy to cope with water stress, isolated soil from extreme temperatures and improving soil humidity, control the presence of weeds and therefore reduce the inputs of herbicides and improve soil fertility. This work aimed to analyse the effect of three different organic mulches [straw (S), grape pruning debris (GPD) and spent mushroom compost (SMC)] and two traditional soil management techniques [herbicide (H) and interrow (IN)] on weed coverage and the spontaneous plant communities’ presence. Data sampling was collected throughout the vine vegetative cycle of 2021 in La Rioja, Spain. The different soil management techniques had a clear effect on weed coverage and his development during the vine vegetative cycle. SMC and H were the treatments with the highest and the lowest coverage percentage, respectively. IN had a delayed weed emergence at the beginning of the vine vegetative cycle, but finally it reached maximum values nearby SMC. GPD and S had similar effects on weed emergence, reaching 25-30% of the maximum coverage values. A total of 29 herbaceous species were identified during the vegetative cycle, some of them very isolated and occasional. Principal component analysis (PCAs) showed a good association between spontaneous species and treatments, furthermore, specific species-treatment associations were found. Moreover, three clear groups of herbaceous communities were identified by cluster analysis. This study provides interesting information about the effect of different alternative soil management on herbaceous plant coverage and weed species communities which could contribute to making more sustainable viticulture.