Cold process soap goes through five stages: weighing, mixing, molding, cutting, and curing. Here is the work behind the bar you use.
1. Weighing the formula
Oils, butters, water, and lye are weighed according to a precise recipe. Changing an oil requires recalculating the formula. This guide outlines workshop procedures; it is not a recipe to be replicated.
2. Mixing and monitoring the batter
Fats are combined with the lye solution. The batter evolves and thickens: the soapmaker monitors its consistency before pouring. Handling precautions are an integral part of the process.
3. Molding, without cooking the batter
In cold process, the batter is not cooked to accelerate its transformation. It does, however, produce heat. In hot process, cooking is used: the difference lies in the method, not in automatic superiority.
4. Unmolding and cutting
When the block is firm enough, it is unmolded and then cut. Weight and batch tracking accompany this step. Small visual differences are due to the cutting process or the pattern.
5. Letting the soap cure
The bars rest before being sold. They lose some of their water content and generally become firmer. The duration depends on the formula and production monitoring; it does not guarantee a specific effect on the skin.
Key takeaways. Cold process soap requires a precise formula and time. Superfatting is another formulation choice, explained separately.