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Cold process is probably the soap maker’s favorite process for handmade soaps. It is very versatile, allowing to create textures, shapes, designs with different colors. The soap product you get is professional grade. And you are in full and complete control of the ingredients you use. In this post, you will find a list of all cold process soap recipes tested and tried in this blog.
What is Cold Process Afterall?
Handmade soap is produced by mixing a mixture of oils with lye water. Cold process is based on this principle, where soap is made with no heat source during saponification, using room temperatures, and the heat released by the chemical reaction itself. The temperature at which the oils and lye water are mixed together needs to be controlled to ensure the produced soap has no issues. However, the only heating necessary is the one to melt solid oils.
Cold process soap creates hard soap bars, whose properties are mostly given by the oils used in the mixture: conditioning, foamy, bubbly, cleansing, mild.
Please, explain about “Trace” and “Gel phase”…
Terms such as “trace” and “gel phase” are always mentioned when speaking about cold process. “Trace” means that all the oils have been emulsified with the lye water – however, saponification is only partially done by now. “Gel phase” happens afterwards “trace”, when the soap batter has been poured into molds and saponification continues. The rest of the saponification reaction releases heat, and when this heat is high enough, we say that the soap reached “gel phase” – soap looks brilliant, gelatinous, like gel.
Reaching gel phase makes the soap less opaque and with brighter colors, therefore, many soapmakers make sure the “gel pahse” takes place.
… And “soda ash”? What Is It? How to avoid it?
Soda ash is a white powder that forms on the surface of soap, it looks a bit like white ash powder. It is the product of unsaponified lye reacting with carbon dioxide present in the air, during the saponification. The powder is completely harmless, but may be a nuissance for your pretty colors and designs.
Using less water (water discount, or a bigger lye concentration) and gel phase (you need to thermically isolate your soap mold) are means to avoid soda ash. Other ways to avoid it: sprinkle your soap with alcohol or leave your soap in soap molds for a few days after the soap solidifies (only possible if you are using individual soap molds).