In every class I teach, as soon Rose oil is mentioned I know the question will be asked about the differences between Rose Otto and Rose Absolute, and rightly so. They are often both available from the same vendor under “Rose Oil” and many recipes will specify using one or the other. They vary in aroma, color, viscosity and price. If you don’t know the difference, it can be very confusing. I’m here to de-confuse you.
Below is an explanation of the different methods of extracting rose essential oils and hence, the different products born of each method.
There are three methods of extracting the essential oil from rose petals:
1. Hydro Distillation: Rose petals (usually from the Rosa damascena plant) are placed in a container with pure water then slowly heated. The warm water allows the flowers to release their essential oil. The steam and essential oil pass through a cooling process and finally to a container where the oils float on the surface. The essential oil is collected and sold as Rose Otto. The watery liquid that remains is called Rose Hydrosol. Rose Otto tends to have a clear to very pale yellow color and a light, gentle aroma which lends itself well to wearing it as a perfume. This product crystalizes when cold due to plant waxes.
2. Solvent Extraction: Solvent extraction happens in three stages, which I’ll share in a highly abbreviated version. First, the rose petals are placed in a drum with an organic solvent, usually hexane or toluene, and rotated. This draws out the aromatic portion of the petals. When the hexane has evaporated, what remains is a thick, waxy substance called a concrete (not used by aromatherapists). Next, the waxes and non-aromatic components are filtered out of the concrete with ethanol alcohol, leaving behind an aromatic liquid we call Rose Absolute.
Solvent extraction gives a greater yield than distillation which is why Rose Absolute tends to be less expensive than Rose Otto. The color of Rose absolute tends to be a dark orange to red with an intense, pungent rose aroma. It is preferred by perfumers and said to be closer in fragrance to the flower than an otto.
3. Supercritical Carbon Dioxide Extraction: This is an expensive process involving some highly sophisticated equipment, but which offers superior oil. The rose oil extracted by this is considered truest to the original fragrance in the flower, and may be called an absolute or a CO2.
Do you have a personal preference? Which rose oil do you like, Rose Otto or Rose Absolute?