Savonnerie De l’Atlantique, a double tradition :

Marseille soap Soap production in Nantes  

Marseille soap
The name Savon de Marseille (Marseille soap) is historically linked to a technique for making soap created in Marseille. This process was discovered when in 1789, Nicolas Leblanc, a chemist from Marseille, developed a method for producing caustic soda to replace the alkalis traditionally used in soaps, carbonates in particular. From then on oils were saponified and the soap cleaned to remove impurities and concentrated with up to 63% fatty acids (68% active matter). The process consists of combining caustic soda and a fatty substance (saponification), then separating the glycerin, cleaning the soap and finishing the raw soap (concentration of the soap in the lye phase). The “Marseille” method is that used by the Master Soapmakers.
This traditional method is different from the modern technique developed in the second half of the 20th century. It is much simpler and consists of combining soda with fatty acids, which are produced from fat that has been chemically processed.
In March 2003, the DGCCRF*, France’s Competition Council, approved regulations concerning the name Savon de Marseille, which defined the conditions of use for the name Savon de Marseille and ensured that only soap produced using the “Marseille” method can be called as such.

*DGCCRF : Direction Générale de la Concurrence , de la Consommation et de la Répression des Fraudes