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Vineyard geology?bedrock and overlying soils?is widely supposed to help explain the typicity of wine from a particular area, though there has been little analysis of how this might come about. Such an evaluation is attempted here. Geology does underpin some of the physical parameters that affect vine performance, but in an indirect way and the factors are commonly manipulated artificially. A direct geochemical influence on wine flavour is widely inferred but remains undemonstrated. The popular model of nutrients being taken up by the vine and persisting to be tasted in the finished wine is untenable. The amounts that reach the fermenting must are minuscule, bear little relation to the substrate composition, and can be further complicated by contamination and fining. In the final wine these inorganic nutrients normally exist in concentrations far below human recognition thresholds and are ?swamped? by the organic secondary metabolites that do dominate wine flavour. Hence, any geochemical influence, like that of the physical factors, has to be highly complex and indirect. The notion of being able to taste the vineyard geology in the wine?a go?t de terroir?is a romantic notion which makes good journalistic copy and is manifestly a powerful marketing tactic, but it is wholly anecdotal and in any literal way is scientifically impossible. Thus critical evaluation leads to the conclusion that the role of geology tends to be exaggerated.authorsversionPeer reviewe

Tasting minerality in wine is highly fashionable, but it is unclear what this involves. The present review outlines published work concerning how minerality in wine is perceived and conceptualised by wine professionals and consumers. Studies investigating physico-chemical sources of perceived minerality in wine are reviewed also. Unusually, for a wine sensory descriptor, the term frequently is taken to imply a genesis: the sensation is the taste of minerals in the wine that were transported through the vine from the vineyard rocks and soils. Recent studies exploring tasters’ definitions of minerality in wine support this notion. However, there are reasons why this cannot be. First, minerals in wine are nutrient elements that are related distantly only to vineyard geological minerals. Second, mineral nutrients in wine normally have minuscule concentrations and generally lack flavour. Results of reviewed studies overall demonstrate marked variability in both wine professionals’ and wine consumers’ definitions and sensory-based judgments of minerality in wine, although there is some consensus in terms of the other wine attributes that associate with the term mineral. The main wine composition predictors of perceived minerality involve a complex combination of organic compounds dependent on grape ripeness and/or derived from wine fermentations and redox status.