This is the third article in the LJO Explains series — a glossary of cosmetic terms, decoded honestly. Because understanding what is on your label is the first step to understanding what is on your skin.

Most of us use a dozen cosmetic products every day without giving much thought to how they were made — or what the words on the label mean. Emulsified. pH balanced. Surfactant-free. Anhydrous. These terms describe the architecture of a product — the decisions made during formulation that determine how it feels, how it performs, and how it interacts with your skin.

Understanding formulation language puts you in a much stronger position as a consumer — and helps you see past marketing claims to the actual chemistry behind a product.

This instalment of LJO Explains decodes the language of cosmetic formulation.

Saponification

What it means: Saponification is the chemical reaction that produces soap. When a fat or oil (containing fatty acids) is combined with a strong alkali — such as sodium hydroxide (for bar soap) or potassium hydroxide (for liquid soap) — a chemical reaction occurs that transforms both ingredients into two entirely new substances: soap (the sodium or potassium salt of fatty acids) and glycerol (a natural humectant).

Why it matters: Saponification is not simply mixing ingredients — it is a complete chemical transformation. The original fat and the original alkali cease to exist as separate compounds. What remains is something fundamentally different: a molecule that is capable of attracting both water and oil simultaneously — which is what makes soap an effective cleanser.

Cold vs. hot saponification:

  • Hot process — the reaction is accelerated using heat. Faster, but destroys many of the beneficial compounds in the original oils.
  • Cold process — the reaction occurs at ambient temperature, preserving the natural vitamins, fatty acids, antioxidants, and glycerol in the finished soap.

Le Joyau d'Olive: We use exclusively cold process saponification — curing our soaps for five full months to allow the reaction to complete naturally. The result is a bar that retains the full nutritional profile of virgin olive oil, along with naturally produced glycerol that keeps skin hydrated after washing.

Emulsification

What it means: Emulsification is the process of combining two immiscible liquids — most commonly water and oil — into a stable, uniform mixture called an emulsion. Left to themselves, oil and water always separate. Emulsification prevents this by introducing an emulsifier — a molecule with one water-loving end and one oil-loving end — that holds the two phases together.

Types of emulsions in skincare:

  • Oil-in-water (O/W) — tiny droplets of oil dispersed in water. Lighter, less greasy feel. Common in lotions and serums.
  • Water-in-oil (W/O) — water droplets dispersed in oil. Richer, more occlusive. Common in heavy creams and ointments.

Le Joyau d'Olive: Our bar soaps are anhydrous — they contain no water in their finished form (the water used during saponification evaporates during the five-month curing process). Emulsification is not required for our soap bars. Our liquid handwash and bodywash, however, are emulsified formulations — carefully balanced to deliver the benefits of olive oil in a liquid format.

Emulsifier

What it means: An emulsifier is an ingredient that stabilises an emulsion — preventing the oil and water phases from separating. Emulsifiers are amphiphilic: one part of the molecule is hydrophilic (attracted to water) and the other is lipophilic (attracted to oil). This dual nature allows them to sit at the interface between oil and water droplets, keeping them evenly dispersed.

Common emulsifiers: Lecithin (from soy or sunflower), beeswax, cetyl alcohol, glyceryl stearate, and various synthetic emulsifiers including polysorbates and carbomers.

Natural vs. synthetic emulsifiers: Natural emulsifiers (lecithin, beeswax) are generally gentler on the skin and the environment. Synthetic emulsifiers can be more stable and predictable, but some — particularly polysorbates — have raised questions about their effect on the skin barrier over time.

Surfactant

What it means: Surfactant is short for surface-active agent. Surfactants reduce the surface tension of water — allowing it to spread more easily and interact with oils and dirt on the skin. They are the primary cleansing ingredients in most body washes, shampoos, face washes, and liquid soaps.

How they work: Like emulsifiers, surfactants are amphiphilic — one end attracts oil (and the dirt dissolved in it), the other attracts water. When you rinse, the water-loving end pulls the oil-loving end — along with the dirt — away from the skin and down the drain.

The problem with synthetic surfactants: The most common surfactants in commercial products — sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES) — are highly effective cleansers. They are also associated with skin barrier disruption, irritation, and sensitisation. They strip not only dirt but also the natural oils and proteins that keep the skin barrier intact.

Le Joyau d'Olive: Real soap — produced through saponification — is itself a surfactant. The sodium salts of fatty acids produced during the reaction have natural surface-active properties. But unlike SLS and SLES, these naturally derived surfactants are gentle, biodegradable, and skin-compatible. Our soaps cleanse without stripping. That is the difference between a true soap and a synthetic detergent.

pH Balance

What it means: pH is a measure of the acidity or alkalinity of a substance, on a scale from 0 to 14. A pH of 7 is neutral (pure water). Below 7 is acidic; above 7 is alkaline. The skin's natural pH — the "acid mantle" — ranges from approximately 4.5 to 5.5, making it slightly acidic.

Why the skin's pH matters: The acid mantle is a critical component of the skin's barrier function. It inhibits the growth of harmful bacteria and fungi, supports the skin microbiome, and maintains the integrity of the skin barrier. Products with a pH significantly higher or lower than the skin's natural range can disrupt the acid mantle, leading to dryness, irritation, and increased susceptibility to infection.

The soap pH question: Traditional soap made through saponification has an alkaline pH — typically between 9 and 10. This is higher than the skin's natural pH, and some skincare professionals point to this as a reason to prefer pH-balanced synthetic cleansers. However, the skin has a natural buffering capacity — it can restore its acid mantle within 30–90 minutes of washing with a properly formulated natural soap. The five-month curing process at Le Joyau d'Olive allows saponification to complete fully, resulting in a gentler, well-buffered bar.

Preservative

What it means: A preservative is an ingredient that prevents microbial growth — bacteria, fungi, and yeast — in a cosmetic product, extending its shelf life and preventing contamination.

Why preservation matters: Any product that contains water is vulnerable to microbial contamination. Without adequate preservation, water-containing products can become breeding grounds for harmful bacteria within days or weeks of opening. Preservation is not optional — it is a safety requirement.

Common preservatives: Parabens (methylparaben, propylparaben), phenoxyethanol, benzyl alcohol, potassium sorbate, sodium benzoate, and certain essential oils with antimicrobial properties.

The paraben debate: Parabens have been used as cosmetic preservatives for decades — and are among the most studied preservative systems available. Concerns arose from studies suggesting oestrogenic activity; however, regulatory bodies in Europe, the US, and globally have consistently found them safe at concentrations used in cosmetics. That said, many consumers prefer to avoid them — and many brands have reformulated accordingly.

Le Joyau d'Olive: Our bar soaps are anhydrous — they contain no water and therefore do not require preservatives. The absence of water eliminates the primary environment in which microbial growth occurs. Our liquid formulations use carefully chosen preservation systems that meet our natural standards.

Chelating Agent

What it means: A chelating agent binds to metal ions — particularly calcium, magnesium, and iron — that are naturally present in water and can destabilise cosmetic formulas, reduce the effectiveness of preservatives, and cause discolouration or rancidity in products.

Common chelating agents: EDTA (ethylenediaminetetraacetic acid), phytic acid (from rice or corn), and citric acid.

Le Joyau d'Olive: The natural phenolic compounds in virgin olive oil — particularly oleuropein — have mild chelating properties, contributing to the stability and shelf life of our soap without the need for synthetic chelating agents.

Viscosity Modifier

What it means: A viscosity modifier adjusts the thickness or flow of a cosmetic product — making it thicker or thinner as required. Viscosity affects how a product feels on the skin, how it is dispensed, and how it spreads.

Common viscosity modifiers: Carbomer (thickens water-based products), xanthan gum, hydroxyethylcellulose, salt (thickens surfactant-based products), and waxes (for anhydrous formulations).

Solubiliser

What it means: A solubiliser helps oil-based ingredients dissolve in water-based formulas — preventing the separation of insoluble compounds (such as essential oils) in water-based products like toners or micellar waters.

Common solubilisers: Polysorbate 20, PEG-40 hydrogenated castor oil, and certain plant-derived glycols.

Active Concentration

What it means: The active concentration of an ingredient is the percentage at which it is present in a formula. This matters because most active ingredients have a minimum effective concentration — below which they produce no measurable benefit — and a maximum safe concentration — above which they may cause irritation or adverse effects.

Why this matters: Many products list impressive active ingredients prominently on their packaging — but include them at concentrations far too low to produce any clinical effect. This is a common form of ingredient marketing that misleads consumers.

Le Joyau d'Olive: Our soaps contain 100% of their named ingredients at the concentrations nature provides — not diluted, not padded. Virgin olive oil is not a trace ingredient. It is the entire base.

Anhydrous

What it means: Anhydrous means containing no water. Anhydrous formulations include oils, balms, butters, waxes, and — relevantly — bar soaps that have completed their curing process.

Why anhydrous formulations are notable: The absence of water eliminates the need for preservatives, extends shelf life significantly, and often results in a more concentrated, efficacious product. Anhydrous products are also inherently more sustainable — they are lighter, require less packaging, and generate less waste.

Le Joyau d'Olive: Our bar soaps are fully anhydrous after five months of curing — all residual water from the saponification process has evaporated, leaving a pure, concentrated, preservative-free bar.

Aqueous

What it means: Aqueous means water-based. The majority of skincare products — serums, toners, lotions, creams, and liquid cleansers — are aqueous formulations. Water is typically listed first in an INCI ingredient list (as "Aqua") because it is present in the highest concentration.

Why this matters: When water appears first on an ingredient list, it means water is the primary ingredient. This is not inherently a problem — many effective formulations are water-based — but it is useful context when evaluating the concentration of other active ingredients in the formula.

In Summary

Cosmetic formulation is a science — and like any science, its language can be learned. Understanding the difference between a surfactant and a true soap, between an anhydrous and an aqueous formula, between cold process and hot process saponification gives you the tools to evaluate what you are actually putting on your skin.

At Le Joyau d'Olive, we have nothing to hide in our formulation. Four ingredients. Cold process. Five months of patience. An anhydrous bar with no need for preservatives, emulsifiers, or synthetic surfactants.

That is the science behind our soap. It is also its simplicity.

This is part of the LJO Explains series — a glossary of cosmetic terms, decoded honestly.
Next in the series: LJO Explains: Eczema, TEWL, Microbiome — Understanding Your Skin's Language