What does clean smell like? What if the fragrance you want to create is that of a sweet-smelling, yet poisonous, flower? In his Scientific Artistry of Fragrances SCITalk, Dr Ellwood led us by the nose.

When Dr Simon Ellwood spoke about creating a fragrance, it sounded like a musical composition or a painting. The flavourist, sitting before a palette of 1,500 fragrance ingredients. Each occupies a different note on the register: the top notes, the middle ones, and the bottom.

To the outsider, this seems impossibly vast and daunting. The Head of Health & Wellbeing Centre of Excellence – Fragrance and Active Beauty Division at Givaudan mentioned that Persil resolved to come up with ‘the smell of clean’ for its detergents in the late 1950s.

But what should clean smell like? Should it be the green, citrusy aromas of this laundry detergent, the smell of mint, or the antiseptic at the hospital?

To make choosing smells slightly less daunting for flavourists and perfumers, they are at least split into odour families such as citrus, floral, green, fruity, spicy, musky, and woody. Some of these ingredients are natural, some are inspired by nature, and others come from petrochemicals and synthetic materials.

The delicious-smelling musk deer.

Deer gland perfume

One of the smells you may have sprayed on your person – one sibling in this odour family – has peculiar origins. The pleasant, powdery smell known as musk was originally extracted from the caudal gland of the male musk deer and from the civet cat.

But as the Colognoisseur website notes, as many as 50 musk deer would have to be killed to obtain one kilogramme of these nodules. Now, killing a load of deer and cats for a few bottles of perfume may not have seemed unethical several centuries ago, but it also wasn’t sustainable or cost-effective. It became clear that a synthetic musk was needed.

When the synthetic musk discovery came in 1888, it was a chance discovery. Albert Bauer had been looking to make explosives when a distinctive smell came instead, along with the scent of opportunity.

>> Read about the science behind your cosmetics

Dior recreated the woodland notes of Lily of the valley.

Do you like the smell of jasmine?

Dr Ellwood’s talk laid bare not only the vastness of everything we smell, but also the ingenuity of those who recreate these odours. In terms of breadth of smell, neroli oil – which is taken from the blossom of a bitter orange – has floral, citrus, fresh, and sweet odours, with notes of mint and caraway. Similarly, and yet dissimilarly, jasmine’s odour families are broken down into sweet, floral, fresh, and fruity, and – jarringly – intensely fecal.

The ingenuity of flavourists is exemplified by lily of the valley. The woodland, bell-shaped flowers are known for their evocative smell, but all parts of the plant are poisonous. Despite this, French company Dior synthetically recreated the lily of the valley smell in its Diorissimo perfume in 1956 using hydroxycitronellal, which is described by the Good Scents Company as having ‘a sweet floral odour with citrus and melon undertones’.

Cyanide smells like almonds, but you might not want to eat it.

Of course, as Dr Ellwood noted, synthetic flavours can only ever get so close to the real thing – an imperfect facsimile. However, the mere fact that chemists have recreated deer musk, lily of the valley, and the prized ambergris from sperm whales to create the fragrances we love is almost as extraordinary as the smells themselves.

‘Fragrance,’ he said, ‘will always be the confluence of the artistry of the perfumer and the chemist.

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Little machines that blend makeup tailored for your skin alone… Technology that details the tiny creatures walking on your face… The cosmetic revolution is coming, and Dr Barbara Brockway told us all about it.

Max Huber burnt his face. The lab experiment left him scarred, and he couldn’t find a way to heal it. So, he turned to the sea. Inspired by the regenerative powers of seaweed, he conducted experiment after experiment – 6,000 in all – until he created his miracle broth in 1965. You might know this moisturiser as Crème de la Mer.

A rocket scientist in the world of cosmetics seems strange, but when you interrogate it, it isn’t strange at all. As Dr Barbara Brockway, a scientific advisor in cosmetics and personal care, explained in our latest SCItalk, cosmetics hang from the many branches of science.

Engineering, computer science, maths, biology, chemistry, statistics, artificial intelligence, and bioinformatics are among the disciplines that create the creams you knead into your face, the sprays that stun your hair in place. They say it takes a village to raise a child, and it takes an army of scientists to formulate all the creams, gels, lotions, body milks, and sprays in your cupboard.

Some say sea kelp can be used to treat everything from diabetes, cardiovascular diseases, and cancer, to repairing your nails and skin.

There is a reason why the chemistry behind these products is so advanced. If you sell bread, it is made to last a week. If you make a moisturising cream, it is formulated to last three years. To make sure it does that, chemists test it at elevated temperatures to speed up the time frame. They conduct vibration tests and freeze-thaw tests to measure its stability.

Dr Brockway likened the process of bringing a product to market to a game of snakes and ladders. If you climb enough ladders, you could take your own miracle brew to market within 10 months.

But expectations are high, and the product must delight the user. Think of the teenager who empties a half a can of Lynx Africa into his armpit, or the perfume that is a dream inhaled. Each smell she likened to a musical composition.

But these formulators are not struggling artists. Perfumers and cosmetic chemists – these bottlers of love and longing and loss – can earn a fortune. Dr Brockway’s quick calculation provided a glimpse of the lucre.

Take 15kg of the bulk cream you mixed on your kitchen table. That same cream could be turned into 1,000 15ml bottles, each sold for £78. So, just 15kg of product could fetch £78,000. So, it’s easy to see why the global beauty market is worth $483 billion (£427 billion), with the UK market alone worth £7.8 billion – more than the furniture industry.

Smart mirror, mirror, on the wall… 

It’s unsurprising that an industry of such value and scientific breadth embraces the latest technologies, from those found in our phones to advances in genetics and the omics revolution.

Already, the digital world has left the makeup tester behind. Smart mirrors overlay virtual makeup, recommend products for your complexion, and even detect skin conditions. Small machines that look like coffee-makes blend bespoke makeup. Indeed, Dr Brockway noted that Yves Saint Laurent has created a blender that produces up to 15,000 different shades.

Even blockchain has elbowed into the act. It is being used to make sure that a product’s ingredients aren’t changed in between batches. By showing customers every time-stamped link of the supply chain, companies can prove that their products are organic or ethically sourced. The reason why blockchain is significant here is that, once recorded, the data stored cannot be amended.

At first glance, proving the provenance of materials to customers might seem like a marketing ploy, but this is also being done in response to the increasing fussiness of the consumer.

Collagen is the main component of connective tissue.

Dr Brockway said all brands are now under pressure to incorporate sustainability into their business practices. The younger age group is also looking for more organic, vegan-friendly ingredients, and businesses have had to respond.

For example, microbial fermentation is being used instead of roosters’ coxcombs to create hyaluronic acid. Similarly, Geltor claims to have created the first ever biodesigned vegan human collagen for skincare (HumaColl21®). Such collagen is usually provided by our friends the fish.

These advances are significant, certainly to the life expectancies of roosters and fish, but of such ingredients revolutions are not made. Other forces will shake the industry.

Meditating on omics

Back in the 1970s, scientists thought the microbes that live on our skin were simple, but next-generation DNA technology reveals that thousands of species of bacteria live on our skin (a pleasant thought). Dr Brockway says these microbes tell us about our lifestyles – to the point that they even know if you own a pet.

So, what is the significance of this? Developments in DNA technology and omics (various disciplines in biology including genomics, proteomics, metagenomics, and metabolomics) mean we can now get not just a snapshot, but an entire picture of what’s going on on your face.

‘Thanks to omics we really know what’s now going on with our skin and see what our products are doing,’ Dr Brockway said. ‘We know the target better. We know which collagens, out of the 263, we need to encourage.’

We are learning more and more about how our skin behaves. And those time-honoured potions and lotions espoused by our grandparents – it will make sense soon, not just why they work, but why they work for some and not for others. In cosmetics, we are leaving the era of checkers and entering the age of chess.

This is the first of three cosmetic SCItalks between now and Christmas. Register now for the Scientific artistry of fragrances.