Olive oil soap: how is it made and what makes it different?

In the finished soap, the olive oil is no longer present as an oil but has been chemically converted. That is the key difference from creams and lotions, in which olive oil remains an oil. What olive oil does in caring formulas is covered in our guide to olive oil in skincare; this article is only about soap.

Many olive oil soaps also contain other oils, such as coconut or laurel berry oil, as well as glycerin, water and perhaps fragrance. The order on the ingredient list shows what dominates: ingredients above 1% are listed in descending order of concentration.

Two methods are common:

• Cold process: oil and lye are mixed at moderate temperatures, poured into moulds and then left to mature.
• Hot process: the mixture is heated so saponification is completed during production.

In a correctly calculated recipe, the lye is fully used up in the reaction, so no free lye remains in the finished soap. Many recipes deliberately use slightly more oil than the lye can saponify; this is known as ‘superfat’. Whether the glycerin stays in the soap depends on the process. Industrial soaps are also made from ready-made soap noodles.

None of these names guarantees a particular recipe on its own. The INCI list shows which oils have actually been used.

Bar soap usually comes with little packaging and lasts a long time if stored correctly. Liquid soap is more hygienic for shared use, for example at a washbasin, and is easy to dose with a pump, but it contains a lot of water and therefore usually a preservative.

Liquid ‘Castile soap’ is often sold as a concentrate and diluted before use. Many modern shower gels, by contrast, are not soaps at all but are based on synthetic surfactants. The ingredient list tells you which is which.

Soaps with a high olive oil content are relatively soft at first and are therefore often left to mature for longer than soaps made with a blend of oils. How long depends on the recipe, the bar size and the manufacturer’s process; traditional Aleppo soaps, for example, mature for a particularly long time.

A well-matured bar wears down more slowly in use. Because a soap keeps losing a little moisture after maturing, the weight declared on the pack is planned together with the manufacturer.

Body and hands: the classic use. Lather, rinse well and apply a body lotion afterwards if you like.

Face: soap is alkaline, while the skin’s surface is slightly acidic. Some people use olive oil soap on their face without problems; others find it too tight. Try it on a small area first.

Hair: washing hair with soap often leaves it feeling rough or dull, especially with hard water. For daily hair washing, a shampoo made for it is usually the simpler choice.

For skin conditions, please ask a doctor for advice.

Soap removes oil and dirt effectively. Many people with normal or oily skin find this pleasant, while dry or sensitive facial skin may feel tight afterwards. Others find soaps with a high share of unsaponified oil (superfat) too rich for the face.

• Do a patch test first, for example along the jawline, over a few days.
• Use lukewarm water, lather briefly and rinse thoroughly.
• Pat your face dry and follow with a face cream.
• If your skin feels tight, use soap less often or switch to a milder cleanser.

Olive oil soap is a cleansing product, not a treatment. If you have a skin condition such as acne or eczema, please ask a doctor or dermatologist for advice.

Soap is made by saponifying oils with lye, so it is alkaline by nature. The glycerin that forms during saponification stays in traditionally made soap and helps the skin feel soft after washing.

Syndets (synthetic detergents) and most shower gels are based on surfactants whose pH can be set to around 5.5, close to that of the skin.

Whether your skin feels dry also depends on your skin type, water hardness and how often you wash. A body lotion after showering helps to keep the skin supple.

The label must show, among other things: the name and address of the Responsible Person, the nominal quantity, the minimum durability date or PAO symbol, the batch number, the function where not obvious, precautions, and the ingredient list. Source: Regulation (EC) No 1223/2009, Article 19.

Paper wraps and cardboard boxes are common because the soap can continue to breathe. Shrink film offers more protection during transport but can trap moisture. Claims such as ‘mild’ must be supported by evidence. Our olive oil soap for retailers: packaging and labelling on request.