Projects / Programmes
Influence of heavy metal ions on shelf life of white wines
| Code |
Science |
Field |
Subfield |
| 4.03.07 |
Biotechnical sciences |
Plant production |
Technology of vegetal origin food |
| Code |
Science |
Field |
| T430 |
Technological sciences |
Food and drink technology |
| Code |
Science |
Field |
| 4.01 |
Agricultural and Veterinary Sciences |
Agriculture, Forestry and Fisheries |
metal ion, copper, aroma, wine quality, atypical ageing, esters, terpenols
Researchers (15)
Organisations (3)
Abstract
Wine is the agricultural product with the highest added value and for numerous wine producing countries, wine production is an important vector of economic development, particularly for rural area. Within a context of market globalisation, the preservation of wine quality has become more important as ever for wine economy in order to keep and develop market share. The respect of environment during the production has also become an important criteria of wine purchase for numerous consumers. Maintaining or improving wine quality respecting strict environmental rules of production in order to obtain certifications that in tun can improve wine sales is not always easy. The use of copper in agriculture and particularly in viticulture is currently subject to intense debates at scientific and political levels in Europe due to its importance in the booming organic farming. From a scientific point of view, most of the studies have focused on the toxicity of copper found in vineyards soil regarding the environment and very few on wine quality. This lack of investigation mainly comes from the fact that most of copper found in grape juice is eliminated during the fermentation. However, recent studies showed that even at trace level as generally found in wine, copper could contribute to alter wine composition and sensory profile, particularly when it is in combination with other metal ion found in wine such as iron and manganese. White wines are generally more sensitive to such alterations due to their lower antioxidant capacities. One major issue found in numerous entry level white wines available in stores, which are also the most sold, is the fast loss of aromatic freshness and fruitiness happening only few months after bottling and being released on the market. This loss of freshness can be followed by the apparition of notes of mothballs, furniture varnish, acacia blossom, wet wool, and dirty dishrag, also called atypical ageing (ATA). While a couple of studies suggest the potential involvment of metal ions regarding the development of ATA and the fast loss of fruity aroma in white wines, this topic has been overrall poorly investigated and knowledge remains very limited.
Therefore, this project aims to investigate the link between iron, copper and manganese, the development of atypical ageing (ATA) off-flavours and the degradation of markers of wine aromatic quality such as esters and terpenols. The first main activity will correspond to establish potential correlations between all these parameters through a chemical survey of a set of commercial Slovene white wines. The second work-package will focus on determining how metal ions interact with wine matrix to potentially favour ATA development and loss of esters and terpenols. Objective indicators that would allow producers to detect risky situation regarding wine aromatic quality evolution will be set. Finally, the third workpackage will aim to to establish practices that will limit such a risk in the cellar and in the vineyard. A special attention will be paid to water stress, yield and grape maturity in the vineyard, and fining product and yeast starters in the cellar. These investigations should lead to a better understanding of wine ageing chemistry and in turn to improve the shelf life of white wines. Improving wine quality in a context of climate change respecting the environment and new consumer demands has recently become a priority for the wine industry around the world. It is the reason why Laffort, one of the world leader company in the field of oenology, want to invest in research on this topic co-funding this project.
Significance for science
The influence of metal-ion on wine chemistry remains poorly understood. The recent outputs on the synergistic effect of metal ion present at trace level in wine-like medium opens very interesting perspective to develop knowledge in the field of wine ageing chemistry in direct relationship with wine quality. This project will aim to make a break-trough in that field focusing on white wine aromatic quality but the results could open wider perspective about metal ion and wine sensory profile evolution. Metal ions reactivity in wine medium could potentially be the X factor to better understand the diversity of wine style with regard to their geographic origin or terroir. This topic has been of high interest for numerous wine scientist for decades. The outputs of this project could also be extended to general food chemistry focusing on the preservation of aromatic quality of food product. Therefore, this project could be a real break-through in the field of oenology and food science.
Significance for the country
Though wine is not essential to human survival, wine is a mark of cultural heritage; it is an ancient and celebrated beverage; and lastly it is a global industry which today represents about 200 billion € of trade. It is the agricultural product with the highest added value and for numerous wine producing countries, wine production is an important vector of economic development, particularly for rural area. Within a context of market globalisation, the preservation of wine quality has become more important as ever for wine economy in order to keep and develop market share. The main applicative aim of this project is to find relevant, sustainable, applicable and convenient solutions in the cellar and in the vineyard to extent the shelf life of white wines. It particularly targets the first market segment which includes the white wine the most sold in Slovenia and around the world. This project also aims to improve metal-ion management, particularly copper, in order to improve white wine quality in Slovenia and around the world. Having a better understanding on how copper influence wine quality is an important question for the wine industry in a context of climate change and increasing consumers demand for organic wines that involve higher usage of copper. This project will benefit to the reputation of the Slovenian wine industry and will help limiting the economic loss due to ATA spoilage and fast degradation of wine aromatic quality. The high interest for this project of a company as important for the field as Laffort, a world leader in the production of oenological product, reflects a real need for the wine industry world-wide.
