neat soap

Also known as: kettle soap

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Last updated

July 1, 2026

Quick Summary

"Neat soap" refers to molten soap produced during manufacturing, specifically after it has settled and separated from impurities like nigre and lye. This purified soap is the primary material used to create bars, flakes, beads, and powders.12

The process of creating neat soap typically involves boiling natural fats or oils with a caustic alkali solution, such as sodium hydroxide. This reaction, called saponification, produces soap and glycerin. To separate the glycerin, the mixture is treated with brine, causing the soap to salt out into a curdy mass, while the glycerin dissolves in the salty liquid. Further boiling and washing steps remove remaining impurities, resulting in neat soap with a consistent composition, usually around 70% soap and 30% water.2

Historically, soap has been known for over 2,300 years, with early production methods involving animal fats and plant ashes.3

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liquid crystal
Liquid crystal compounds
…a lamellar phase, also called neat soap. In this case it is important to recognize that soap molecules have a dual chemical nature. One end of the molecule (the hydrocarbon tail) is attracted to oil, while the other end (the polar head) attaches itself to water. When soap is placed…
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…a lamellar phase, also called neat soap. In this case it is important to recognize that soap molecules have a dual chemical nature. One end of the molecule (the hydrocarbon tail) is attracted to oil, while the other end (the polar head) attaches itself to water. When soap is placed…
Read More

soap and detergent
Boiling process
Its object is to produce neat soap in purified condition, free from glycerin. Neat soap is the starting material for making bars, flakes, beads, and powders. The boiling process is conducted in a series of steps called changes; these occur in the kettle (called the pan in Great Britain).
Read More
Its object is to produce neat soap in purified condition, free from glycerin. Neat soap is the starting material for making bars, flakes, beads, and powders. The boiling process is conducted in a series of steps called changes; these occur in the kettle (called the pan in Great Britain).
Read More