IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 The effect of wine cork closures on volatile sulfur compounds during accelerated post-bottle ageing in Shiraz wines

The effect of wine cork closures on volatile sulfur compounds during accelerated post-bottle ageing in Shiraz wines

Abstract

Reduced off-flavour is an organoleptic defect due to an excess of volatile sulfur compounds (VSC) in wine and often happening in Shiraz wines. This off-flavour is a direct consequence of the lack of oxygen flow during winemaking and bottle storage. Therefore, wine closure could have a direct impact on the formation of VSC due to the oxygen transfer rate that can modulate their levels. Even if dimethylsulfide (DMS) contributes to reduced off-flavor, it is also a fruity note enhancer in wine and its evolution during wine ageing is not well understood. Until now, we knew that DMS was mainly released from S-methylmethionine and DMSO during wine ageing. Chemical equilibrium between DMS and all the DMS precursors called also DMS potential (DMSP) are not well understood and the influence of the closure permeability has never been investigated. In this study, we studied (a) the evolution of 7 VSC in Shiraz wines by GC-MS/MS according to several closure permeabilities and (b) the equilibrium between DMS-DMSP during accelerated wine ageing. In practice, 6 Shiraz wines were collected from 2 regions in France and bottled under anaeroby conditions with 4 different wine closures made with micro-agglomerated cork exhibiting 4 different oxygen transfer rates. VSC and DMSP were analyzed by HS-SPME-GC-MS/MS at the beginning and after 3 months of storage at 35°C. Globally, the total amount of VSC increased after 3 months of accelerated ageing, corroborating that reduced off-flavour can appear during bottle ageing due to hypothetic decomplexation mechanisms. Among the 7 analyzed VSC, only 3 (H2S, MeSH and DMS) showed significant changes in their levels during wine ageing. Indeed, the levels of H2S increased by a factor of 1.4 ± 0.5. The type of closure seemed to modulate the production of H2S, but no evident relation has been found. For MeSH, an overall increase was observed and was equal in average to a factor of 5.2 ± 2.7. For DMS, a significant increase of a factor of 5.1 ± 2.5 was observed and a general tendancy appeared : the most permeable closures induced a smaller production of DMS during ageing. It appeared that DMS could escape through the closure and that the loss was proportional to the permeability of the closure. Since DMS came from the chemical degradation of DMSP, we studied the evolution of DMSP during wine ageing. As expected, DMSP levels decreased during ageing by a factor of 1.5 ± 0.4 and we observed a correlation with closure permeability : the most permeable closures favoured the degradation of DMSP, suggesting that oxygen level could play a role in this mechanism. Under accelerated ageing conditions, VSC levels increased significantly and could reinforce the reduced off-flavour of Shiraz wines. For the first time, closure permeability and so, indirectly oxygen level, could play a role in the DMSP degradation. From a technical point of view, closures with a very low permeability seem to be recommended to preserve DMS.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

De La Burgade Rémi1, Nolleau Valérie1, Godet Teddy1, Galy Nicolas2, Tixador Dimitri2, Loisel Christophe2, Sommerer Nicolas1 and Roland Aurélie1

1SPO, Université Montpellier, INRAE, Institut Agro, Montpellier, France
2DIAM Bouchage

Contact the author

Keywords

volatile sulfur compounds, bottle ageing, wine closure, reduction, oxygen transfer rate

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Grapevine yield estimation in a context of climate change: the GraY model

Grapevine yield is a key indicator to assess the impacts of climate change and the relevance of adaptation strategies in a vineyard landscape. At this scale, a yield model should use a number of parameters and input data in relation to the information available and be able to reproduce vineyard management decisions (e.g. soil and canopy management, irrigation). In this study, we used data from six experimental sites in Southern France (cv. Syrah) to calibrate a model of grapevine yield limited by water constraint (GraY). Each yield component (bud fertility, number of berries per bunch, berry weight) was calculated as a function of the soil water availability simulated by the WaLIS water balance model at critical phenological phases. The model was then evaluated in 10 grapegrowers’ plots, covering a diversity of biophysical and technical contexts (soil type, canopy size, irrigation, cover crop). We identified three critical periods for yield formation: after flowering on the previous year for the number of bunches and berries, around pre-veraison and post-veraison of the same year for mean berry weight. Yields were simulated with a model efficiency (EF) of 0.62 (NRMSE = 0.28). Bud fertility and number of berries per bunch were more accurately simulated (EF = 0.90 and 0.77, NRMSE = 0.06 and 0.10, respectively) than berry weight (EF = -0.31, NRMSE = 0.17). Model efficiency on the on-farm plots reached 0.71 (NRMSE = 0.37) simulating yields from 1 to 8 kg/plant. The GraY model is an original model estimating grapevine yield evolution on the basis of water availability under future climatic conditions.  It allows to evaluate the effects of various adaptation levers such as planting density, cover crop management, fruit/leaf ratio, shading and irrigation, in various production contexts.

A spatial explicit inventory of EU wine protected designation of origin to support decision making in a changing climate

Winemaking areas recognized as protected designations of origin (PDOs) shape important economic, environmental and cultural values that are tied to closely defined geographic locations. To preserve wine products and wine-growing practices adopted in different PDOs these areas are strictly regulated by legal specifications. However, quality viticulture is increasingly under pressure from climate change, which is altering the local conditions of many winegrowing areas. Therefore, maintaining traditional wine products will require the adoption of tailored adaptation strategies, including possible changes in the legal regulation of protected wines. To this end, it is necessary to have a comprehensive knowledge on PDOs including their extension, products and allowed practices. While there have been efforts to build databases that summarize the characteristics for individual wine PDO areas and to quantify the related effects of climate change, much information is still included only in the official documentation of the EU geographical indication register and has never been collected in a comprehensive manner. With this study we aim at filling this gap by building a spatial inventory of European wine PDOs that supports decision making in viticulture in the context of climate change. To map and characterize European wine PDOs, we analysed their legal documents and extracted relevant information useful for climate change adaptation. The output consists of a comprehensive geographical dataset that identifies the boundaries of all 1200 European wine PDOs at unprecedented spatial resolution and includes a set of legally binding regulations, such as authorized vine varieties, maximum yields and planting density. The inventory will allow researchers to analyse the impacts of climate change on European wine PDOs and support decision makers in developing tailored adaptation strategies. This includes, among others, the evaluation of new vineyard site selection, the expansion of cultivated varieties or the authorization of irrigation in vineyards.

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)

Simulating climate change impact on viticultural systems in historical and emergent vineyards

Global climate change affects regional climates and hold implications for wine growing regions worldwide. Although winegrowers are constantly adapting to internal and external factors, it seems relevant to develop tools, which will allow them to better define actual and future agro-climatic potentials. Within this context, we develop a modelling approach, able to simulate the impact of environmental conditions and constraints on vine behaviour and to highlight potential adaptation strategies according to different climate change scenarios. Our modeling approach, named SEVE (Simulating Environmental impacts on Viticultural Ecosystems), provides a generic modeling framework for simulating grapevine growth and berry ripening under different conditions and constraints (slope, aspect, soil type, climate variability…) as well as production strategies and adaptation rules according to climate change scenarios. Each activity is represented by an autonomous agent able to react and adapt its reaction to the variability of environmental constraints. Using this model, we have recently analyzed the evolution of vineyards’ exposure to climatic risks (frost, pathogen risk, heat wave) and the adaptation strategies potentially implemented by the winegrowers. This approach, implemented for two climate change scenarios, has been initiated in France on traditional (Loire Valley) and emerging (Brittany) vineyards. The objective is to identify the time horizons of adaptations and new opportunities in these two regions. Carried out in collaboration with wine growers, this approach aims to better understand the variability of climate change impacts at local scale in the medium and long term.

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