Typology: where does the smell of cosmetics come from?

Unlike many cosmetic products, Typology treatments contain no fragrance.

This choice of formulation is based on a desire to limit exposure to certain substances known for their allergenic potential. Indeed, while the addition of fragrances in cosmetics makes it possible to obtain pleasant scents, these molecules are very often allergenic and can trigger skin reactions such as redness, irritation or itching, particularly in sensitive skin. In the absence of these masking agents, the odour perceived therefore corresponds directly to that of the raw materials used.

The scent of Typology treatments therefore comes largely from the ingredients themselves, particularly when they are of natural origin.

Plant oils, for example, have their own distinct olfactory signatures : plum oil, notably present in our Nourishing Face Cream L42, naturally has an almond-like note, while other oils may exhibit more woody scents depending on their lipid profile. Hydrolats and certain essential oils also contribute to the overall scent of formulations. For instance, lavender essential oil is recognisable by its floral fragrance, while tea tree oil has a more medicinal, herbaceous odour, and lemon or sweet orange essential oil brings fresh, zesty notes. Others, such as geranium essential oil, have a slightly rose-like floral scent, and patchouli essential oil is characterised by deeper, earthier notes.

Certain cosmetic active ingredients are also known for their characteristic odour. This is particularly true of sulphur, which is used for its purifying properties but has a particularly strong smell. To reduce its olfactory impact, masking agents such as zinc ricinoleate can be incorporated in order to partially capture these volatile compounds. This is a formulation choice we have made for our Blemish Face Scrub L73. Other ingredients, such as lactic acid, present in our Enlarged Pores and Blackheads Mask L71, also have a recognisable odour, sometimes associated with slightly acidic notes, linked to their chemical structure. These odours, although unexpected, are intrinsic to the molecules used.

The preservative systems can also influence a product’s odour. Benzyl alcohol, for example, has a naturally almond-like smell, while O-cymen-5-ol can evoke more synthetic notes. These compounds are, however, used at low concentrations to ensure the microbiological stability of formulations. Their olfactory perception, although secondary, can nonetheless be detected in the absence of added fragrance.

Good to know : O-cymen-5-ol is notably one of the components of our 9-Ingredient Face Cream D41.

In cleansing products, the odour can also be linked to surfactants, that is to say the agents responsible for the cleansing action. Certain surfactants, such as cetyl phosphate, may have a somewhat unpleasant smell. This perception becomes more pronounced as their concentration increases in cleansers, which is significantly higher than in moisturising creams. This is why, at Typology, we have chosen to incorporate essential oils into our Purifying Facial Cleansing Gel L12 and into our Exfoliating Facial Cleansing Gel L13.

Moreover, the surfactants used in cleansing products generally have a high HLB (Hydrophilic–Lipophilic Balance), which means that they have a strong affinity for water. This property allows them to dissolve easily in the aqueous phase and to form micelles capable of surrounding and removing lipophilic impurities, such as sebum and make-up residues. This micellar structure and their hydrophilic nature also promote the dispersion of certain odorous molecules in water, which can make their smell more noticeable, particularly when they are used at high concentrations in cleansing formulations.

Conversely, the emulsifiers present in creams have a more intermediate HLB, enabling them to stabilise both an aqueous phase and an oil phase. They position themselves at the interface between these two phases, with a hydrophilic part oriented towards the water and a lipophilic part oriented towards the fatty substances. This organisation influences the olfactory perception of the formulation: the odorous compounds, which are often lipophilic, are partly retained in the oil phase or trapped within the structure of the emulsion, which can reduce their volatility and therefore their immediate perception.

In other words, with the same composition, a given odorous molecule may appear more pronounced in a cleansing gel than in a cream, due to the way it is distributed and released within the formula.

Finally, it is important to recall that the perception of an odour remains largely subjective and depends greatly on what we are accustomed to. Many everyday products contain fragrances designed to standardise their smell and to mask the sometimes more “raw” odours of the raw materials. Conversely, a fragrance‑free formula reveals the intrinsic smell of its ingredients, whether these are vegetable oils, active substances or certain excipients. These odours may then seem surprising, simply because they fall outside our usual olfactory frame of reference. It is not an indication of a formulation defect, nor a sign that the product has deteriorated, but rather a reflection of its composition and of formulation choices aimed at limiting unnecessary additives, particularly those likely to increase the risk of irritation in sensitive skin.

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• MAGGI F. & al. Essential oils as natural sources of fragrance compounds for cosmetics and cosmeceuticals. Molecules (2021).

• MAZZUCCO A. & al. Odor masking, stability and sensoriality: Researching background agents in complex systems for infinite solutions. International Journal of Chemistry and Research (2020).

• ROMERO A. & al. Sensorial evaluation and aroma of vegetable oils. Oil and Oilseed Processing: Opportunities and Challenges (2021).