Flavor sensations, origin

In this review an original and unique approach was undertaken to unite the notions "heterocycles" and "wine principles." Indeed, it is astonishing that natural wines contain numerous heterocyclic principles in varying quantities (as low as nanograms ) that contribute to flavor, smell, taste, and aftertaste ("finish") sensations, all of which are characteristic of the different grape types. During aging and maturation of the wines in barrels and bottles, manifold additional heterocycles are formed or extracted. The odor threshold plays an important role in all cases, which is ultimately dependent on the chirality centers of the isomers involved in aroma. 

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