Naturally occurring alcohol with pronounced earthy-musty odor and taste, It is perceived as a typical soil odor, causing, among other things, the smell of molds and occurs especially when rain starts after a long time dryness or on freshly plowed soil. Geosmin is from microorganisms bstimmter bacteria (Myxobacteria and Streptomyces species) that live mainly in the soil. Geosmin is also responsible for the typical smell of the juice beet.
In the wine is one earthy Low-grade clay can be regarded as positive and often the characteristic of certain French red wines (see below) Stinkerl ). If stronger, this indicates different wine faults as Geranienton. corked or horse sweat out. The human sense of smell reacts highly sensitively to geosmin; the Perceptual threshold is 0.1 Ppb (parts per billion).