Soda soap is a traditional cleaning product made from lard, water and sodium hydroxide (caustic soda). In many areas of Spain it is made by replacing lard with olive oil, known in some regions as castile soap.
Soda soap was the soap that was used all over the world before soap started to be manufactured and distributed from the industrial sector. It was brewed in many homes by hand and is still widely used because of its potential skin benefits and its recipe. biodegradable. This soap can be used for personal hygiene and also, with slight variations, for laundry and household cleaning in general.
The characteristic ingredient of this soap is Caustic Soda, or just bland. This name corresponds to sodium hydroxide, a highly corrosive substance that can be found in drugstores and soap-making product distributors. In its origins, soda was not used, but the ashes of a plant, saponaria, which contained large amounts of sodium hydroxide.
lard, olive oil or any other fat that is used (coconut, palm, sunflower, etc.) .
o Water It is the third ingredient in traditional soda soap and is mainly used as a dissolving agent.
From the reaction of fatty acids and sodium hydroxide, known as saponification reaction, sodium salts of fatty acids are formed, the characteristic molecules of soap that act as surface-active agents capable of dissolving hydrophobic substances in water. This reaction also forms glycerin, which has emollient and moisturizing properties on the skin, and water.
Recipe and elaboration
Today you can find soda soap produced on an industrial level, some manufacturers make it by hand and there are also those who continue to make it in their own home. There is no universal recipe, but there are as many regions of the planet.
In the traditional form of soda soap made from lard, the water and lard were heated until both were mixed. Then the caustic soda was added little by little without stopping stirring. In the case of using liquid oils, the caustic soda is usually completely dissolved in the water and then the oil is added, stirring continuously.
In any case, the mixture is stirred until it acquires a thick consistency, a sign that the saponification process has been completed. It is then left to dry until it can be cut into portions.Traditional Castile Soap Recipe: Mild soda soap and olive oil that works well for personal hygiene and any other use. 900 g of crude oil, 300 g of water and 115 g of caustic soda. Traditional Recycled Oil Soda Soap Recipe: Best hard soap recipe for laundry and home cleaning. 3 L of water, 3 L of recycled olive oil and 0.5 kg of caustic soda.
Let’s see in this video an example of making Castile soap (soda and olive oil):
Advantages and disadvantages
Some traditional recipes contain more sodium hydroxide than necessary, resulting in a very rough soap. Modern versions are much smoother using a much smaller amount of coolant that can even leave a certain amount of oil unreacted.
The glycerin formed in the saponification process is a mild cleanser that works well for acne-prone skin. Basic recipes do not contain fragrances or other synthetic ingredients that can irritate the skin, so it can be used by people with psoriasis or atopic dermatitis.
An added advantage is that traditional soda soap is a biodegradable product. It’s eco-friendly, relatively inexpensive, and easy to make.
The main disadvantage of soda soap is that it is a strong soap with an alkaline pH, usually between 8 and 9, higher even if a lot of soda is used in its preparation. Another disadvantage is that handling the coolant requires great care due to its high abrasiveness.