Aldehydes are organic compounds characterized by the presence of a carbonyl group (a carbon atom double bonded to an oxygen atom) at the end of a carbon chain, with the general formula RCHO. In perfumery, aldehydes are synthetic chemicals that are valued for their distinct scents and their ability to enhance other fragrances.
The scent profile of aldehydes can vary widely but they are generally known for their sharp, clean, and bright qualities. Some aldehydes contribute a sparkling, fizzy quality, often likened to the effervescence of freshly opened champagne. Others may have floral, citrusy, or waxy nuances, making them versatile in creating various fragrance notes. Famous for their use in iconic perfumes such as Chanel No. 5, aldehydes add a certain abstract, airy lift and can act as fixatives to stabilize other more volatile scents.
In terms of scent intensity, aldehydes can range from very potent to mild and are often used at the top of the perfume's fragrance pyramid. This placement allows their impact to be felt immediately upon application, giving an initial burst of freshness before mellowing or blending into the heart and base notes of the fragrance. Their inclusion can transform a perfume, adding layers of complexity and a modern twist.