Excessive crossbreeding of roses has led to hybrids losing their scent. Only specific species are for fragrances – technologies and chemical processes
Rose extraction methods
Rose extraction occurs from rose petals through several processes.Steam distillation, solvent extraction, or supercritical carbon dioxide extraction. Extracting rose as an essential oil requires a lot of plant material: rose petals, steamed or water distilled. The result is expensive, but it is the purest form of oil available. In addition, the essential oil will vary in its aroma depending upon which species of rose it is extracted from.
Steam distillation is the most widely used technology when compared with the other two, and it results in absolute. Solvent extraction technology doesn’t require heat during the process. It is produced from rose concrete – the solid, waxy residue created from immersing rose petals in solvent – at two temperatures, respectively under twenty-five and twenty degrees; using two concentrations (96%, 80%) of ethanol as solvent. In addition, the chemical composition of the absolute mainly consists of phenylethyl alcohol, citronellol, geraniol, nerol, 1-nonadecene, methyl eugenol, eugenol, nonadecane and benzyl alcohol.
The advantages of using supercritical extraction
A relative newcomer to the market is supercritical extraction that uses carbon dioxide; which comprises the steps of cleaning, freeze-drying, extraction and molecular distillation. This technique requires lower temperatures and a short heating time, avoiding the risk of oxidization and rancidification of oil caused by higher temperature. The acid value of the oil is lowered due to the molecular distillation. Furthermore, the advantages of using supercritical extraction is that it collects no impurities and the purity and efficiency rates are higher; creating an oil which more closely resembles the chemical make-up of the plant. The distillation of the rose can also produce a hydrosol. A water-based product that is steam or water distilled in much the same way as the essential oil; except that the water is drawn off and used. Alternatively, rose can be infused in vegetable oil, a slow and traditional method more cost effective.
The cost of rose oil derived from extraction is very expensive as it takes about two hundred and fifty pounds of petals to make an ounce of oil. For this reason, the distillation of rose often occurs with similarly scented oils such as geraniol from geraniums, or even synthetic phenylethanol, one the most commonly available chiral alcohols.
The use of flowers and roses in perfumery
For centuries, rose has been the most important crop in the floriculture industry. The genus Rosa includes 200 different species and more than 18,000 cultivars rely their economic value in the use of the petals as a source of natural fragrances and flavorings. In addition, rose is prevalent all across the world in all shapes and sizes and in a variety of colors and smells. However, the excessive crossbreeding of roses has led to hybrid roses losing their scent. For this reason, only certain species of roses make it into the fragrances.
Rose petals represent a viable system in the application of modern genomics technologies in the search for novel genes involved in fragrance production. Among the most scented species collected by perfumers are Rosa damascene, present in Turkey and Bulgaria, and Rosa Centifolia. Rose de Mai or painter’s rose, also known as the hundred-leafed rose; grown around Grasse in the south of France and generally considered to produce the highest quality scent in the world.
The scientific research behind perfumery
A flower scent in general is a composite character brought about by a complex mixture of volatile molecules of low molecular mass. For many years, research into flower fragrances focused on their chemical elucidation. As a result, they identified hundreds of compounds. Most of these compounds belong in three major biosynthetic pathways: phenylpropanoids, fatty acid derivatives, and terpenoids. As highlighted above, the scent of a perfumed rose is dropped from many commercially available rose flowers in favor of longevity and color.
In 2015, researchers found a gene called RhNUDX1, an enzyme that is responsible for triggering the production geraniol, the key ingredient in rose oil, in the petals. This discovery will make it easier for rose breeders to select plants for their fragrance. Eventually, they may be able to directly insert the gene into existing roses to create genetically modified variants. As described by perfumer, François Demachy, the world’s most recognizable and genuinely positive scent is the smell of roses.
Jo Malone London – Red roses cologne
Inspired by the blend of the world’s most exquisite roses; accompanied by a hint of crushed violet leaves and a hint of lemon. There are seven varieties of roses within the Red Roses collection. From which Bulgarian, Turkish, Damascus, May and French rose stand out. This collection consists of a cologne, a candle and a diffuser. The scent of cut flowers opens its olfactory pyramid. Juicy and lively notes of lemon, with a green accent of violet leaves. Sweet honey notes close the pyramid. The British brand is working to channel more sustainable practices to lessen the environmental impact of their releases. From recycled and recyclable packaging to the use of renewable energy and responsibly sourced ingredients.
Tom Ford – Rose D’Amalfi
Rose D’Amalfi is a floral, unisex and layerable fragrance launched in 2021 under the Private Rose Garden Collection. A trilogy of fragrances – Rose de Chine, Rose D’Amalfi and Rose de Russie. The inspiration of each one comes from a flower from Ford’s personal garden. Rose D’Amalfi features the distillation ‘rose on rose’ from the Amalfi coast. Italian bergamot in the top notes, and a blend of spicy pink peppercorns with almond-shaped heliotrope.
Kilian Paris – Good Girl Gone Bad
The rose of Mai is the protagonist of Good Girl Gone Bad by Kilian. Enriched by orange blossoms, tuberose, Egyptian jasmine sambac, and narcissus. Perfumer, Alberto Morillas, topped this blend with a milk toffee touch. A lot of attention goes into each bottle of Kilian Paris refillable perfume. A distinctive white lacquer adorns and engraves each side with a ceramic fresco representing the original sin. Every perfume bottle by Kilian Paris is refillable indefinitely.
Frederic Malle – Rose Tonnerre
Perfumer, Edouard Fléchier, had the intuition to blend the contrasting sweetness of the Turkish rose with the woodsy sharpness of blue chamomile, patchouli, vetiver and castoreum. The creation of Rose Tonnerre, previously Une Rose, comes from the combination of the earthy scent of truffles and the lees of red wine. Frederic Malle’s concept for Editions de Parfums was to assemble some of the greatest perfume talents in the industry. Therefore establishing a publishing house of fragrance, commissioning the perfumers to move away from the constraints and demands of mass market.