Origin of petrichor
The main component responsible for the aroma is geosmin, a terpenoid alcohol produced by bacteria of the genus Streptomyces and by other soil microorganisms.
Conditions that generate it
When the soil is dry, bacteria form spores and produce geosmin. Rain triggers the release of this compound as it moistens the earth, and it also dissolves other compounds that contribute to the smell, such as plant oils and molecules from plants.
Importance
Petrichor is perceived by most people and is associated with freshness in the air. It has no harmful effects; it is simply a chemical signal indicating the presence of moisture and microbial activity in the soil.
Fun facts
- The term "petrichor" comes from the Greek "petra" (stone) and "ichor" (the fluid that flows through the gods in mythology)
- Studies indicate that geosmin can be detected by humans at concentrations as low as 5 parts per billion.
- The smell is more intense after heavy rains or in soils rich in organic matter.


¡Qué interesante explicación! Me encanta cómo la ciencia detrás del petricor revela la colaboración entre bacterias y la lluvia para crear ese aroma tan especial.
Siempre me ha fascinado ese olor después de la lluvia, ahora entiendo mejor su origen. ¿Alguna vez se ha intentado replicarlo en perfumes o productos similares?