Cold saponification requires the use of 2 main ingredients: oils (or butters), which make up the fats, and soda (sodium hydroxide) used as a strong base. Once these compounds have been blended, soap-making can begin…
The transformation of fats into soap is the result of a chemical reaction. For several minutes at low temperature, soda gradually transforms vegetable oils and/or butters into soap. The advantage of working with temperatures below 30°C is that the properties of the ingredients used are preserved. During cold saponification, the mixture takes on the texture of a soap paste of varying thickness: this is the “trace” stage.
The latter is particularly important for the artisan soap-maker, who must ensure the consistency of his soap. When the trace appears, it’s also time to add the other natural ingredients that will make up cold-saponified soap: essential oils, mineral or vegetable colorants, plant powders, essential oils, honeys…
Once the soap dough has reached the desired consistency, it is poured into a mold and placed in the refrigerator to harden (generally for 24 to 48 hours). After demolding, comes the “curing” stage. The soap then sits in a dry, well-ventilated place for at least 4 weeks. The cure is important because it finalizes the saponification process, resulting in a softer soap that melts more slowly.