Hanseniaspora in wine-making: their genetic modification and potential role in acid modulation

The 5th edition of the International Conference Series on Wine Active Compounds (WAC) will be held from 29 June to 1 July 2022 (Dijon, France). All authors with accepted abstracts will have the possibility to publish either a short 4-pages article or a...

Previous research on the fruity character of red wines highlighted the role of esters. Literature provides evidence that, besides these esters, other compounds that are not necessarily volatiles may have an important impact on the overall aroma of wine, contributing to a modulation of its global aromatic expression. The goal of this work was to assess the olfactory consequences of a mixture between esters and proanthocyanidic tannins, through sensory and physico-chemical approaches.
Sensory analysis of numerous aromatic reconstitutions, including triangular tests, detection thresholds, and sensory profiles, were conducted in order to evaluate the sensory impact of tannins on red wine esters perception.

Le monde vitivinicole est de plus en plus concerné par la question paysagère : l’enjeu est de taille puisqu’il s’agit de la survie de l’image positive dont bénéficient les Appellations d’Origine Contrôlée. Les paysages sont composés d’éléments qui renvoient à des références socioculturelles fortes, susceptibles de modeler l’image d’un produit et d’en déterminer à notoriété et le prix. Dans un monde médiatisé comme le nôtre, le visuel construit l’arrière-plan des représentations mentales associées à toute marchandise ; et pour les aliments, produits de la terre, ce visuel est forcément paysager.

In the study of terroir, a separate analysis of its many component factors can be of great help in accurately identifying a vineyard’s natural elements that impact wine quality and typicity. This research used a dedicated pluri-disciplinary approach to investigate the ecological characteristics, including geology and geographical features, of 14 vineyards that produce Gewürztraminer and Sauvignon Blanc cultivars in the alpine Alto Adige DOC wine region. Both the geopedological method using Vineyards Geological Identity (VGI) and the new Solar Radiaton Identity (SRI) topoclimatic classification method were used to provide analytical measurements and qualitative/quantitative characterisations. In addition, wide-ranging targeted and untargeted oenological and chemical analyses were carried out on grapes, musts and wines to correlate the soils’ geomineral and physical conditions with the biochemical properties of their fruits and wines. The research identified strong correlations between vineyard geo-identity and wine biofingerprint, confirming a mineral traceability of strontium rubidium ratio and some minerals distinctive to the local geology, such as K, Ca, Ag, Ba and Mn.  The study also discovered that particular geomineral and physical soil conditions of the studied vineyards are related to the different amount of amino acids, primary varietal aromas and polyphenols found in grapes, musts and wines. The research confirmed that winemaking technologies support oenological quality, although in some cases, human practices can overpower certain characteristic elements in wine, erasing the typical imprint left by the vineyards’ natural terroir, which becomes less traceable. Terroir abiotic ecological factors and vineyard identity can be classified in detail using the new VGI and SRI analysis methods to discover interrelationships between geo-pedological and topoclimatic conditions that impact wine quality. These methods are also helpful in identifying which ecological elements are exclusive to a particular vineyard or wine sub-region.

The UV-C light enhances oxidative processes in wine. Increasing the dose of UV-C can lead to olfactoric, gustatoric and colour changes in wine. These changes are triggered by a series of photochemical reactions such as degradation of esters, the formation of odour-active substances such as 2 aminoacetophenone through the photooxidation of amino acids. Ultimately, these reactions can lead to a reduced wine quality.