Where does glycerin in soap come from

Handmade soap, soap by saponification, cold process soap

Glycerin appears during the creation of a soap. Soap is created through a process called saponification, which is a reaction between an alkaline agent (e.g. caustic soda, potash, ash, etc.) and a fatty substance (vegetable oil – coconut, olive, etc.). – or other fat such as animal fat, for example).

This saponification has two forms of operation: hot or cold saponification.

Hot saponification consists of heating the ingredients (oil and caustic soda, for example) for several hours at about 100°C. This speeds up the saponification process because the drying (or curing) time can be reduced to just one day.

Cold saponification takes place at room temperature. The resulting mixture should be left to dry for approximately one month. A cold saponified soap can be easily recognized by the SAF logo on the craftsman’s website (European standards).

So after saponification (hot or cold), a washing base is formed, also called “soap”, as well as glycerine.


But what exactly is glycerine?

Glycerine is an essential element in any fat and is obtained at the same time as soap during saponification. Therefore, it is a natural part of any soap.

Then, the following can be done with glycerin:

Remove it: in the Marseille soap, for example, the glycerine is removed by washing the soap paste.
Leave it : our soap, for example, contains natural glycerin from the mixture of various oils
Add it: other soaps have had glycerin added which may be of vegetable or animal origin, or worse, petroleum or synthetic.

To find out if your soap has glycerin added, it will appear in the INCI (International Nomenclature of Cosmetic Ingredients) ingredient list under the name – Glycerin or Glycerol. In our case we leave it, it does not appear in the ingredients.

However, it is very difficult to determine the origin of the glycerin because it appears under the same INCI name. This name is the same for vegetable glycerin (palm oil, olive oil), for synthetic glycerin (from petroleum products) and for glycerin from animal fats! For this reason, in some cosmetic scoring applications, glycerin may appear (erroneously) as an ingredient possibly derived from palm oil.


And in my body, does glycerin have an impact?

Leaving, removing or adding glycerin to soap will inevitably have a direct impact on your skin.

In a hot saponified soap, the resulting mixture is rinsed off with salt water. This method removes the remaining soda, which is harmful to the skin. On the other hand, doing this also removes glycerin, which is beneficial to our skin. That is why hot saponified soaps have an exfoliating effect. Therefore, it is not necessarily ideal for people with sensitive, irritated or fragile skin.

The mixture, for a soap obtained by cold saponification, is not heated. This allows the benefits and properties of the oils to be maintained because the ingredients remain more or less at room temperature (below 60°).


Natural glycerin has moisturizing and beneficial properties for our skin. In our soap, we have chosen to keep it because of its properties. In addition to these benefits, our soap is overfatted (8%) thanks to a surplus of non-saponified oil. This allows our soap to deeply nourish the skin, protect it by leaving a film on the skin and is suitable for all skin types, even the most sensitive…


Isn’t glycerin bad for my pipes?

Many recipes for household products recommend using a glycerin-free soap because it can cause clogged machine pipes or shower or bath drains. However, these precautions apply more specifically to glycerin that would be added, especially if it is present in large amounts.

Therefore, it is perfectly possible to use our soap, soap shavings, or any other soap with natural glycerin to make your household clothes and products. All you have to do is simply run your machine once a month without a load, with soda crystals (about two tablespoons) and at high temperature (60 degrees minimum).

Eventually, if you notice that soap residue clogs the drain of your shower or bath, you can also pour soda crystals into it.


Can glycerin damage my clothes?

If you wash your clothes at home with a soap containing glycerin, which is natural of course, it does not affect your clothes in any way, on the contrary.

Glycerin has softening properties, so just like on skin, it can soften and protect clothes (especially wool clothes). It also promotes washing because it can dissolve certain difficult stains and can also be effective in lengthening a garment that would have shrunk in the wash.

If you are likely to have allergic reactions to certain detergents, you can wash your own clothes with a soap containing natural vegetable glycerin.


Can the choice of my soap have an impact on the environment?

Absolutely. The way a soap is made and the ingredients it contains can have an ecological impact. To be an informed and conscious consumer, it is important to know some facts before buying a soap.

First of all, it is better to choose a solid soap. Because it generates less waste, its impact on the planet is much less. It requires little or no packaging. Our soap, for example, is packaged in fully biodegradable cane paper and can also be found in bulk at some of our points of sale, or by contacting us directly – no bottles = less plastic!

Secondly, the way in which a soap is made is very important. Hot saponification requires on the one hand a lot of energy to heat the ingredients and on the other hand a lot of water to wash the soap and remove the excess soda. Remember, it is during this step that glycerin is also extracted. Cold saponification, on the other hand, is a slow process that requires little energy. It is also not necessary to wash the soap because the soda is no longer present. This represents a real energy and water saving that will not be dumped into nature.

In addition to the initial production, the type of oil chosen as grease to make the soap plays an important role. All unsustainable oils should be avoided. Let’s take palm oil as an example. This oil is not in itself bad for the skin, but on the other hand it contributes strongly to deforestation. Palm oil is listed as sodium palmate or kernelate by the INCI. The oil chosen may also have an ethical cost because some soaps add animal fats listed by the INCI.


To return to glycerin, if added to the soap, it can be synthetic and therefore derived from petroleum products. Its impact is not necessarily negligible, and we repeat again: it is better to prefer soaps (and all products in general) that contain natural glycerin of plant origin (sustainable).


Unfortunately, as mentioned above, the list of ingredients alone does not say whether the glycerine contained in a soap is of synthetic, animal or vegetable origin. It is up to the consumer to determine this and seek or even question the brand if it does not play the game of transparency.


So should I choose a soap with or without glycerin?

We believe you should choose a soap that contains glycerine, and especially glycerine from vegetable oils. On the other hand, we should be careful with the one or the ones used, since not all of them are the same in terms of ecological impact (and effects on the skin).

Cold saponified soaps are much better in terms of environmental protection due to the manufacturing process than most other soaps. So you could also kill two birds with one stone: glycerin and cold saponification.

Therefore, we advise you to choose quality cold saponified soaps that contain long-lasting natural glycerine, that respect your skin and protect the environment.

Source : https://www.comme-avant.bio/

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