In a previous article, we told you about the opportunities offered by the synthesis for the perfume industry. Thanks to chemistry, the perfumer has an extraordinary palette of scents, which allows you to enjoy a wide variety of fragrances. This is how many synthetic molecules are used in your compositions, taking you to new olfactory horizons. These famous molecules are often criticized and are unfortunately rarely brought to the forefront by the major brands. However, modern perfumery would be nothing without them… Put on your lab coat and glasses to visit our laboratory and discover the other side of your perfumes.
The art of naturalness through synthesis
What are synthetic molecules?
A synthetic ingredient is a molecule that is artificially manufactured in a laboratory, using various chemical processes. Its purpose is to imitate a natural molecule, to recreate its structure and therefore its smell. Like a recipe, the synthetic compound is made by combining several ingredients. This combination will allow the chemist to come as close as possible to the natural. There are two categories of synthetic molecule. First, there are the totally artificial ones. They do not exist in natural form and are therefore created “from scratch” in the laboratory. This is called total synthesis. There are also molecules created from natural chemical species. We will then slightly modify their initial structures in order to add new odorous properties.
Today, synthetic molecules are widely present in perfume compositions because they have many advantages. There are several thousand of these molecules compared to only a few hundred natural materials.
From chemistry to smell
Thanks to innovation and research, chemists is now able to manufacture as many molecules as they want. However, even if this construction game seems easy, it is far from being as simple to predict the smell of a molecule. Why? Because our nose is a tool full of mysteries that we still have trouble deciphering! This is how two molecular structures which are very close together will not smell the same at all. At the same time, totally dissimilar molecules can be almost identical in smell. For example, vanillin and isovanillin are two compounds that are almost identical in structure. However, one smells like vanilla and the other evokes the scent of bitumen!
The chemist will therefore have to take several parameters into account when creating a molecule. The first is volatility, i.e. the speed at which the odor will evaporate. Then the odor power which is the minimum quantity necessary of product to release an odor.
The olfactory palette of synthetic molecules
Fruity, marine, floral or gourmand, synthetic molecules can reproduce thousands of notes from all olfactory families. Over time and through discoveries, researchers have developed their knowledge and new molecules appeared. Every year, nearly 2,000 molecules are born in laboratories. Here is an overview of the synthetic compounds most commonly used by perfumers, which you will soon know like the back of your hand (and nose)!
The precursor: coumarin
Coumarin is the molecule that paved the way for the introduction of synthetic chemistry in perfumery. It was in 1868 that Wiliam Perkin succeeded for the first time in isolating this compound naturally present in the tonka bean, to reproduce it through synthesis. Coumarin has a typical smell of hay and tobacco. The manufacturing process is then improved, allowing large-scale production. Synthetic coumarin was then used from the end of the 1800s by the largest houses of perfume. Between 1880 and 1900, its price was divided by 8, making it much more affordable. We find coumarin in our eau de parfum vanille to give it a soft and powdery nuance.
Vanillin and ethylvanillin: the super-odorous bean
Ever since vanilla entered the perfume industry, chemists have sought to reproduce it through synthesis to find a cheaper alternative to the natural raw material. After many unsuccessful attempts, vanillin, a natural compound present in the vanilla bean, is isolated. Researchers succeeded in reproducing the natural molecule thanks to the coniferine, which is naturally present in the spruce resin. A few years later, a new molecule with the powerful smell of vanilla was discovered: ethylvanillin, which does not exist in its natural state.
Heliotropine: between pepper and sweetness
The history of this synthetic molecule is unusual. It was first created in the laboratory before being discovered in its natural state. In 1869, two researchers studied the aromatic principle of pepper and created the piperonal with a sweet and powdery smell, halfway between vanilla and almond with floral and delicate notes. A few years later, two other chemists discovered that this compound is in fact naturally present in the heliotrope flower, and therefore they called the molecule heliotropine. It is a material that is widely used in perfumery today because it can have many applications and can be used to reconstitute the notes of certain flowers or to harmonize gourmand accords.
Ionones: lab violet
The violet has always intrigued chemists. They have multiplied tests to capture its smell and reproduce the ionone, a molecule naturally present in the flower but which is impossible to extract. To recreate its structure, they actually have to combine several synthetic compounds. Derivatives with a similar scent are then born, called methylionones. These synthetics ingredients have a very sweet, powdery, floral, and warm smell that is reminiscent of violet candy. They are widely used in floral accords and especially in label rose, our precious and wild fragrance.
Metallic and citrusy: the adlehydes
Aldehydes are synthetic compounds that are naturally present in the peel of citrus fruits. They are used for their olfactory properties, recognisable by their warm, greasy, metallic smell, but also because they bring power, depth and volume to a fragrance. The most famous aldehyde fragrance is probably Chanel N°5. From its creation, the aldehydic accord met with great success and will then used extensively in hygiene and cosmetic products, such as hairspray or body soaps.
Calone: the sea in a bottle
In 1951 researchers discovered calone (technically called Calone 1951), a synthetic material with a particular smell. Originally, chemists were looking to create a food additive with the taste and aroma of watermelon. Instead, they managed to “manufacture” a white powder with a structure similar to the pheromones produced by certain species of algae. In its crystalline form, the calone has a pungent smell. When it is diluted, it gives off its characteristic iodine facet. Its fresh, slightly aniseedy and watery smell evokes iodized air and sea spray. It is found in alõ, our marine and festive fragrance.
Ambrox: amber without sperm whale
From the 1930s, research began to create a synthetic molecule reproducing the smell of ambergris, an ingredient of animal origin. It was finally in 1950 that chemist Max Stoll discovered that by slightly modifying claryol, the structure of clary sage, he obtained a molecule whose fragrance closely resembles that of ambergris. Then called ambrox, this compound will seduce many noses until today, to bring a warm and oriental background to fragrances.
Ethyl-maltol: synthetic delicacy
Etyl-maltol is a synthetic molecule that has been widely used since the 1990s. It is an artificial derivative of maltol, a natural molecule found in cocoa and roasted malt. Ethyl-maltol is a flavour enhancer, and its caramel smell with praline accents is six times more powerful than maltol. This molecule is widely used in perfumery to create gourmand accords with sweet cake or chocolate notes.
This list is far from being exhaustive. There are a multitude of other synthetic molecules that the perfumer can use to reproduce the scents of musk, leather, lily of the valley and many others. Did you know about these chemical compounds?