Perfume masterclass : Rose oil odorant

The most important constituent of rose odorant is phenylethyl alcohol. This compound is primarily responsible for the characteristic fresh, floral, and slightly sweet scent of roses. While rose essential oil and rose absolutes contain a complex mix of hundreds of compounds, phenylethyl alcohol plays a dominant role in giving roses their recognizable fragrance.

Other key components that contribute to rose's complex aroma include citronellol, geraniol, and nerol, which add subtle nuances like sweetness and citrusy undertones. However, phenylethyl alcohol remains the primary contributor to the classic rose scent profile in perfumery and aromatherapy.

1. Phenylethyl Alcohol

• Chemical Structure: Phenylethyl alcohol (PEA) is an aromatic alcohol with the formula $C_8H_{10}O$.
• Odor Profile: Phenylethyl alcohol is known for its delicate, floral, and slightly sweet aroma, which is a key characteristic of rose scent. It has a fresh, rose-like quality that adds a soft, powdery depth to the fragrance.
• Role in Rose Scent: As one of the most important components in rose odorant, phenylethyl alcohol is the main contributor to the natural, fresh quality associated with roses. It provides a floral, subtle sweetness that is highly recognizable in rose-based fragrances.
• Applications: Besides perfumery, phenylethyl alcohol is also used in flavorings, cosmetics, and in the production of other floral notes due to its versatile, gentle scent. It is sometimes synthetically derived to create a stable, consistent version for use in various products.

2. Citronellol

• Chemical Structure: Citronellol is a monoterpenoid alcohol with the formula $C_{10}H_{20}O$.
• Odor Profile: Citronellol has a sweet, fresh, and rosy aroma with a hint of citrus. Its scent is more intense and slightly more lemony or green than phenylethyl alcohol, adding a bright, fresh aspect to the rose scent.
• Role in Rose Scent: In roses, citronellol contributes a vibrant, citrusy freshness that enhances the complexity of the floral profile. It provides a green, slightly fruity quality that balances the sweetness of phenylethyl alcohol.
• Applications: Citronellol is widely used in fragrances, not only in rose compositions but also in other floral blends to add freshness. Due to its insect-repelling properties, it’s also found in some insect repellents and skincare products.

3. Geraniol

• Chemical Structure: Geraniol is an acyclic monoterpenoid and an alcohol with the formula $C_{10}H_{18}O$.
• Odor Profile: Geraniol has a sweet, rose-like aroma with a hint of fruitiness. It’s slightly more intense than citronellol and provides a richer, fruity-floral depth that enhances the overall warmth of the rose scent.
• Role in Rose Scent: Geraniol is critical in creating the balanced complexity of rose fragrance. It deepens the floral notes and gives the rose scent a longer-lasting, rich quality that lingers. It also complements phenylethyl alcohol and citronellol by enhancing the fullness of the fragrance.
• Applications: Geraniol is not only used in perfumes but also as a flavor additive in food. It has antimicrobial and antioxidant properties, making it a popular ingredient in personal care products, aromatherapy, and even insect repellents.
  
  Rose Oil