Have the best Bordeaux wines been drunk already? A reflection on the transient nature of terroir, using case study Australia

Reductive wine fault is characterized by the presence of odors such as rotten eggs or spoiled camembert cheese, originating from hydrogen sulfide (H2S) and methanethiol (MeSH) [1]. These compounds stabilize in polysulfide forms, creating a complex pool of precursors that will revert to both molecules when the environment becomes anoxic [2].

Vers la fin du XX siècle, la vitiviniculture argentine a subi une profonde transformation qualitative atteignant toute la filière. L’analyse de l’évolution de la superficie des vignobles, l’élaboration des vins, la consommation et les exportations, permet de mettre en évidence ces changements. Dans ce contexte, l’origine apparaît comme un outil de force, d’expansion et de succès sur les marchés.

Rotundone, the pepper aroma compound, has been detected in wines made from a large number of grape varieties. However, given the fact that analyzed wines were sourced from different winegrowing regions and seasons, made using different winemaking techniques and at different scales, it remains difficult to assess the real variety potential to produce rotundone.

Alcoholic fermentation is the main step for winemaking, mainly performed by the yeast Saccharomyces cerevisiae. But other wine yeasts called non-Saccharomyces may contribute to alcoholic fermentation and modulate the wine aroma complexity. The recurrent problem with the use of these non-Saccharomyces yeasts is their trend to die off prematurely during alcoholic fermentation, leading to a lack of their interesting aromatic properties searched in the desired wine. This phenomenon appears to be mainly due to interactions with S. cerevisiae. These interactions are often negatives but remain unclear because of the species and strain specific response. Among the non-Saccharomyces yeasts, Lachancea thermotolerans is a wine yeast naturally found in grape must and well known as a great L-lactic acid producer and an aromatic molecules enhancer, but its behavior during alcoholic fermentation can be completely different in co-fermentation with S. cerevisiae in function of strain used.

In many vineyards optimal parcel size exceeds the geospatial complexity that exists in soils and topographic features that influence hydrological properties, sunlight interception and soil depth and texture (available water capacity).