plural geosmins
Definition of geosmin
: a volatile, organic compound C12H22O that is formed especially by soil-dwelling bacteria (such as streptomyces) and aquatic cyanobacteria and that may contribute to the earthy, pleasant odor of petrichor or impart a disagreeable, musty taste and odor to drinking water and certain fish
In the test kitchen, we too have noticed a mysterious muddy flavor in some catfish and tilapia. … When the fish swim in the geosmin-rich water, they consume the compound as they ingest the algae. — Cook's Illustrated Geosmin can be detected by a human nose at miniscule concentrations, as low as just a few parts per trillion, [Kelley Dearing] Smith said.— James Bruggers
Note: Geosmin is a tertiary alcohol having a hydroxyl group (-OH) attached to a carbon atom that has three other carbon atoms attached to it.
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Merriam-Webster unabridged
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Time Traveler for geosmin
The first known use of geosmin was in 1965
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