Introduction

Laundry and toilet soaps, corresponding to the standard generally in use nowadays, are manufactured according to the fully-boiled process starting from 70 - 80 % beef tallow and 20 - 30 % coconut oil or their fatty acids.

As alternative raw materials you can also use palm oil and palm kernel oil. The fully-boiled saponification process allows to separate the glycerin, the unsaponifiable components and an alkali content below 0.1 %. Here a soap having a water content of ab. 34 % is produced. Consequently, it is necessary to dry the soap for the subsequent treatment.

Laundry soaps are dried to a water content of ab. 24 % and toilet soaps to ab. 12 %. At the same time, the finishing process of the soap requires cooling to 20 - 30°C in order to provide the soap with the necessary hardness.

For the manufacture of soft soaps on the basis of potash lye or potash and coconut oil, the semi-boiled process is used. Here the components are heated and mixed. A soap produced according to this procedure still contains all impurities, glycerin and therefore answers inferior demands of quality only. The alkali content is above 0.3 % and the impurities favour oxidation, changes of colour and unpleasant smell.

If heating is renounced at when mixing the fats and alkaline solution, you speak of cold saponification. This reaction takes a few days. At the two latter saponification procedures it is not usual to change the water content by steam drying.