The sensorial perceptions that are induced by tasting a wine are the result of a very large number of factors, most of which are psychophysical rather than chemical in nature; that is to say, they are linked to one’s state of health, one’s mood, one’s environment, one’s attention span and the occasion in which one is tasting that particular wine rather than to the chemical composition of the product itself. Essentially, the same wine, when tasted in different situations (a business lunch vs. a relaxed dinner, a good or bad mood, etc.) can provide not only different emotions but also different perceptions.
This concept can become significant, for example, when pairing a wine with food: whereas, logically, a Champagne should not be matched with a sweet dessert, because it might create strident contrasts of taste and texture, this rule can well be ignored at the end of a romantic dinner, when the Champagne may have quite different functions than that of merely accompanying the dish.
Even if, therefore, the processing that the brain carries out on what it perceives depends on a large number of factors, it is equally certain that the initial stimulus is always determined by the physical and chemical characteristics of the product and by their interaction with specific receptors in our various sense-organs.
One cannot talk about wine, therefore, without being aware of the components that make it up. This is not just an exercice de style or because of some sort of abstract intellectual curiosity, but because of the influence these components have on our initial sensorial sensations, which are then interpreted by our experience and perhaps also modified by other incidental elements.