Macrowine 2021
IVES 9 IVES Conference Series 9 Effect of oenological tannins on wine aroma before and after oxidation: a real-time study by coupling sensory (TDS) and chemical (PTR-ToF-MS) analyses

Effect of oenological tannins on wine aroma before and after oxidation: a real-time study by coupling sensory (TDS) and chemical (PTR-ToF-MS) analyses

Abstract

AIM: Polyphenols are important compounds involved in many chemical and sensory wine features. In winemaking, adding oenological tannins claims to have positive impacts on wine stability, protection from oxidation and aroma persistence. Polyphenols are antioxidant compounds by either scavenging reactive oxygen and nitrogen species or chelating Fe2+ ions (1). However, as tannins oxidation leads to the formation of highly reactive species (i.e. ortho-quinones), it is still unclear if they have an effective role toward oxidation of wine aromas (2). In this work, we aim at studying the effect of two commercial tannins (proanthocyanidins, ellagitannins) on red wine flavour (mainly aroma) before and after air exposition.

METHOD: We coupled a dynamic sensory evaluation technique with a dynamic instrumental nosespace analysis, in order to decipher the impact of oenological tannins on in-vivo aroma release and perception. 17 trained subjects evaluated the temporal dominance of sensations (TDS) of 6 non-oaked Pinot Noir in duplicate, while their nasal cavity was connected to a Proton Transfer Reaction-Time of Flight-Mass Spectrometer (PTR-ToF-MS). Samples followed a Tannin by Oxidation factorial design including the base wine (BW), BW spiked with ellagitannins (BWE) or with proanthocyanidins (BWP), and the three wines after air exposition (OW, OWE, OWP). Each of these 6 samples was evaluated in 3 consecutive sips and this evaluation was duplicated.

RESULTS: TDS sensory results show that red wine oxidation decreases the fruity aroma dominance and increases the dominance of maderised and prune notes (3). The chemical analysis by PTR-MS revealed that the fruity decrease was correlated to the decrease of the fruity ethyl decanoate and the increase of Strecker aldehydes isobutyraldehyde and isovaleraldehyde. The addition of ellagitannins preserves the perception of fruity notes without the appearance of maderised ones after air exposition. This effect was not observed with proanthocyanidins: the TDS curves of OWP was similar to those recorded for OW, both showing dominant maderised and prune aromas, masking the fruity notes. Moreover, the monitoring of in vivo aroma release by PTR-ToF-MS suggests that ellagitannins increase aroma persistence in the non-oxidized wine.

CONCLUSIONS:

Results evidence that the presence of ellagitannins can have a positive impact on the aroma persistence of young red wine and on the preservation of its fruity aroma perception after oxidation. Being red wine oak-barrel ageing a storage in presence of ellagitannins and oxygen, these results could be helpful in managing the sensory shelf-life of fruity red wines with the preservation of these aromas. Indeed, these aromas are able to mask the appearance of oxidative notes, while balancing the sensory contribution of volatiles extracted from wood.

DOI:

Publication date: September 22, 2021

Issue: Macrowine 2021

Type: Article

Authors

Elisabetta Pittari, Isabelle, ANDRIOT (2,3) Luigi, MOIO (1) Jean-Luc, LE QUÉRÉ (2) Pascal, SCHLICH (2,3) Paola, PIOMBINO (1) Francis, CANON (2)

(1) Dept. of Agricultural Science, University of Naples Federico II, Italy (2) Université Bourgogne Franche-Comté, France (3) research infrastructure, ChemoSens facility, Dijon, France, CSGA, AgroSup Dijon, CNRS, INRAE, INRAE, PROBE

Contact the author

Keywords

PTR-ToF-MS – temporal dominance of sensations; proanthocyanidins; ellagitannins; red wine oxidation; oenological tannins

Citation

Related articles…

First step in the preparation of a soil map of the Protected Designation of Origin Valdepeñas (Central, Spain)

This work is a first step to make a map of vineyard soils. The characterization of the soils of the Protected Designation of Origin (D.P.O.) Valdepeñas will allow to group the studied profiles according to their physico-chemical characteristics and the concentrations of most relevant chemical elements. 90 soil profiles were analysed throughout the territory and the soils were sampled and described according to FAO (2006) and classified according to and Soil Taxonomy (2014). All samples were air dried, sieved and some physico-chemical parameters were determined following standard protocols. Also, major and trace elements were analysed by X-ray fluorescence. The statistically study was made using the SPSS program. Trend maps were made using the ArcGIS program. The studied soils have the following average properties: pH, 8.3; electrical conductivity, 0,20 dS/m (low); clay, 18.8% (medium) and CaCO3, 17.1% (high). In the study for the major elements. The major elements of these soils are Si, followed by Ca and Al, with an average content of 203.7 g/kg, 105.5 g/kg and 74.0 g/kg respectively. On the other hand, 27 trace elements have been studied. Of all of them, it can be highlighted the average values of Ba (361.8 mg/kg), Sr (129.3 mg/kg), Rb (83.4 mg/kg), V (74.2 mg/kg) and Ce (70.6 mg/kg). Ba, V and Ce values are higher and the values of Sr and Rb are lower to those found in the literature. The discriminant analysis shows a percentage of grouping of 91%. The content of chemical elements together with the physico-chemical characteristics allows grouping the soils in 4 group according to their order in the classification to Soil Taxonomy; due to the importance of the Calcisols in Castilla-La Mancha, it has been decided to establish them as their own group even if they do not appear in Soil Taxonomy classification.

Different soil types and relief influence the quality of Merlot grapes in a relatively small area in the Vipava Valley (Slovenia) in relation to the vine water status

Besides location and microclimatic conditions, soil plays an important role in the quality of grapes and wine. Soil properties influence…

Analysis of some environmental factors and cultural practices that affect the production and quality of the Manto Negro, Callet and Prensal Blanc varieties

45 non irrigated vineyards distributed in the DO (Denomination) Pla i Llevant de Mallorca and the DO Binissalem Mallorca were used to investigate the characteristics of production and quality and their relationships certain environmental factors and cultural practices. The grape varieties investigated are autochthonous to the island of Mallorca, Manto Negro and Callet as red and Prensal Blanc as white. All plants were measured for four consecutive years in the main production and quality parameters. Among the environmental factors, the type of soil has been studied, more specifically its water retention capacity, the planting density, the age of the vineyard and the level of viral infection. The presence or absence of virus seems to have no effect on any component studied in the varieties studied. For the white variety Prensal Blanc age is negatively correlated with production and the number of bunches, nevertheless it does not cause any effect on the required quality parameters. However, for the red varieties Callet and Manto Negro, the age of the plantation is the variable that best correlates with the quality parameters, therefore the old vines should be the object of preservation by the viticulturists and winemakers in order to guarantee its contribution to the quality of the wines made with these varieties.

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.

The combined effects of climate, soils, and deficit irrigation on yield and quality of Touriga Nacional under high atmospheric demand in the Douro Region

Global warming is one of the biggest environmental, social and economic threats in several viticultural regions. In the Douro Valley, changes are expected in the coming years, namely an increase in temperature and a decrease in precipitation. These changes are likely to have consequences for the production and quality of wine.
The aim of this study was to explore the effects of different soil characteristics combined with several deficit irrigation strategies, managed throughout ETc references and predawn leaf water potentials thresholds, on physiology, yield, and qualitative attributes on the Touriga Nacional variety under years of mild to severe water and heat stress.
The studies were conducted over seven years (2015 to 2021) in two plots of a commercial vineyard located at Quinta do Ataíde (Symington Family Estates) planted in 2011 and 2014 at 170 meters elevation, growing under three water regimes: non-irrigated (NI) and two deficit irrigation strategies (30% and 60% ETc) assessed weekly by Ψpd. The site has an annual rainfall below 500 mm, with high atmospheric demand. Climate data was collected from a weather station, located on site. Berry ripening was followed weekly for fruit analysis. At harvest, yield, vigour and pruning weight per vine were determined from 90 vines by treatment. Each season at veraison the NDVI Index was accessed by a drone. The soils physic-chemistry in the experimental blocs were analysed and grouped by SWHC. Delta C-13 analyses were also performed per treatment in two years.Irrigation had a positive effect on yield per vine, mostly due to an increase in berry and cluster weight, and fertility index through the years. A significant increase in sugar content, colour and phenols was observed with deficit irrigation in some years, but vine vigour related to soil characteristics had by far the greatest impact on quality.