WAC 2022 banner
IVES 9 IVES Conference Series 9 WAC 9 WAC 2022 9 3 - WAC - Oral 9 OTR determination of aged closures: Impact on aroma compounds composition of Sauvignon blanc wines

OTR determination of aged closures: Impact on aroma compounds composition of Sauvignon blanc wines

Abstract

Oxygen transfer rate (OTR) is a technical property of closure, and it modulates the oxygen supply to the wine during its bottle aging. It’s an important parameter to take into account in the analysis of wine aroma evolution. OTR distribution is well documented for new closures, but little research has been published on its determination for aged closures. Initial oxygen release after bottling impacts the composition of wines during the first years of storage), but the link between OTR, sensory perception and aroma composition after many years of aging has not yet been clearly studied. 

This study aimed at assaying the OTR of closures by coulometry as well as the determination of eight revelant volatile molecular markers by GC-MS/MS, including 3-SH, 3-sulfanylhexanol acetate (3-SHA), 4-MSP, Ethyl-2-sulfanylacetate (E2SA), furfurylthiol, methional, phenylacetaldehyde and sotolon. Additional enological parameters were also studied such as dissolved CO2, free and bound SO2, and OD420. Oxidation intensity was also evaluated by a trained panel. The goal was to evaluate the correlation between OTR value of aged closures, concentration of chemical markers and sensory analysis of wine samples. 

We applied this methodology to two set of wines. In a first experiment, a Sauvignon blanc wine sealed with eight different types of closures (natural corks, three microagglomerate corks, two synthetics and two screw caps), was analysed after fourteen years of aging. Our results reveal that, comparing to other stoppers, natural corks exhibit the greatest variability with OTRs values ranging from 0.38 mg/year to 44.9 mg/year. This oxygen transfer rate significantly impacts the balance between thiols vs. other oxidation related compounds.

In a second part, nineteen whites wines from different wineries from a same appellation, sealed with different stoppers (natural and microagglomerate corks) were selected. We demonstrate that regardless of the intrinsic quality of the wine, after six years of aging, OTR plays a fundamental role in the shelf life of the wine. Based on our results, OTRs < 0.3 mg/year seem to delay the premature oxidation characteristics (loss of varietal thiols and increase in oxidation markers). These observations were confirmed by sensory evaluation of wines.

DOI:

Publication date: June 14, 2022

Issue: WAC 2022

Type: Article

Authors

Emilie Suhas, Cécile Thibon, Christophe Loisel, Philippe Darriet, Alexandre Pons

Presenting author

Emilie Suhas – Univ. Bordeaux, INRAE, Bordeaux INP, UR OENOLOGIE, EA 4577, USC 1366, ISVV, F-33140 Villenave d’Ornon,  France

Univ. Bordeaux, INRAE, Bordeaux INP, UR OENOLOGIE, EA 4577, USC 1366, ISVV, F-33140 Villenave d’Ornon,  France | Diam Bouchage, Céret, France | Univ. Bordeaux, INRAE, Bordeaux INP, UR OENOLOGIE, EA 4577, USC 1366, ISVV, F-33140 Villenave d’Ornon | Univ. Bordeaux, INRAE, Bordeaux INP, UR OENOLOGIE, EA 4577, USC 1366, ISVV, F-33140 Villenave d’Ornon,  France -Tonnellerie Seguin Moreau, Cognac France, France 

Contact the author

Keywords

Oxygen transfer rate (OTR)-oxidative stress-shelf life-thiols-sensory analysis

Tags

IVES Conference Series | WAC 2022

Citation

Related articles…

Influence of climatic conditions on grape composition of Tempranillo in La Mancha DO (Spain)

The aim of this work was to analyze the variability in grape composition of the Tempranillo cultivar related to climatic conditions, in La Mancha Designation of Origin. Grape composition (sugar content, total acidity, pH, malic acid, and total and extractable anthocyanins) recorded during ripening, were analysed for the period 2000-2019. The weather conditions at daily time scale, recorded during the same period, were also evaluated. The relationships between grape parameters with climatic variables related to temperature and to water deficits, referring different periods between phenological events along the growing cycle, were evaluated using regression analysis. High variability in grape composition was observed in the period analysed. Total acidity varied between 3.7 and 7.3 gL-1 while malic acid varied between 1.2 and 4 gL-1. The extractable anthocyanins ranged between 526 and 972 mgL-1, and total anthocyanins ranged between 922 and 1388 mgL-1, being the lowest values recorded in the hottest year (2017). Total acidity decreased 0.77 gL-1 for an increase of 100 GDD, while malic acid decrease in 0.42 gL-1 for the same GDD increase, being the period between veraison and harvest the one that seemed to have higher influence on acidity. In addition, it was confirmed that increasing water deficits decreased acidity. Total and extractable anthocyanins increased in about 210 and 105 mgL-1, respectively, with an increase of 100 GDD from veraison to harvest, and the increase in water deficits favour the increase of anthocyanins, both total and extractable anthocyanins. Total and extractable anthocyanins concentration increased in 35 and 22 mgL-1 per an increase of 10 mm in the water deficit. These results can be of interest to understand the potential changes that grapes composition may suffer under future warmer climates.

Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard

Upscaling the integrated terroir zoning through digital soil mapping: a case study in the Designation of Origin Campo de Borja

homogeneous zones by intersecting several partial zonings of major factors that influence vineyard growth. Each of them follows specific process from their corresponding disciplines. Soil zoning specifically refers to a Soil Resource Inventory map that has traditionally been generated by conventional soil mapping methods. These methods have shortcomings in reaching fine cartographic and categorical details and involve significant expenses, which undermines their applicability. A new framework named Digital Soil Mapping has introduced quantitative models by statistical techniques to establish soil-landscape relationships and is able to provide intensive scale cartography.

In the present study, a microzoning at 1:10.000 scale is generated from an initial zoning, where the conventional soil map with polytaxic map units is replaced by a new one from digital techniques that disaggregates them. The comparison between the zonings considers a quantitative evaluation of capability for each Homogeneous Terroir Unit by means of the Viticultural Quality Index and its categorization based on its distribution by map. The spatial intersection of both maps gives rise to a confusion matrix in which the flows of class variations after the substitution are assessed.

The results show a five-fold increase in the number of Homogeneous Terroir Units identified and a larger differentiation among them, evidenced by a wider range in the capability index distribution. Both elements are accompanied by an increase in the detection of areas of higher potential within previously undervalued uniform zones.These features are a direct effect of the improvements brought by Digital Soil Mapping techniques and would verify the advantages of their implementation in the Integrated Terroir zoning. Eventually, such new highly detailed terroir units would benefit precision viticulture and sustainable management practices.

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.

Towards a regional mapping of vine water status based on crowdsourcing observations

Monitoring vine water status is a major challenge for vineyard management because it influences both yield and harvest quality. It is also a challenge at the territorial scale for identifying periods of high water restriction or zones regularly impacted by water stress. This information is of major importance for defining collective strategies, anticipating harvest logistic or applying for irrigation authorisation. At this spatial scale, existing tools and methods for monitoring vine water status are few and often require strong assumptions (e.g. water balance model). This paper proposes to consider a collaborative collection of observations by winegrowers and wine industry stakeholders (crowdsourcing) as an interesting alternative. Indeed, it allows the collection of a large number of field observations while pooling the collection effort. However, the feasibility of such a project and its interest in monitoring vine water status at regional scale has never been tested.

The objective of this article is to explore the possibility of making a regional map of vine water status based on crowdsourcing observations. It is based on the study of the free mobile application ApeX-Vigne, which allows the collection of observations about vine shoot growth. This information is easy to collect and can be considered, under certain conditions, as a proxy for vine water status. This article presents the first results obtained from the nearly 18,000 observations collected by winegrowers and wine industry stakeholders during 2019, 2020 and 2021 seasons. It presents the vine shoot growth maps obtained at regional scale and their evolution over the three vintages studied. It also proposes an analysis of the factors that favoured the number of observations collected and those that favoured their quality. These results open up new perspectives for monitoring vine water status at a regional scale but above they provide references for other crowdsourcing projects in viticulture.