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close this bookHow to Make? An Improved Soap .. Not just for more Foam (GTZ, 1993, 71 p.)
close this folderC. Saponification of simple fats
View the documentC.I. Peanut oil
View the documentC.II. Copra oil
View the documentC.III. Cotton oil
View the documentC.IV. Shea butter
View the documentC.V. Palm oil
View the documentC.VI. Palmkernel oil
View the documentC.VII. Tallows (cow and mutton)
View the documentC.VIII. Fat (pork)
View the documentC.IX. Neem oil
View the documentC.X. Pourghere oil
View the documentC.XI. Castor oil
View the documentC.XII. Sesame oil

C.VIII. Fat (pork)

It is obtained through melting (cooking) of pork fat.

Physical and chemical characteristics:

Density at 15 °C:

0,914 - 0,922

Solidification point:

22 to 32 °C

Iodine number:


Saponification value:

193 - 202

INS Factor:

123 - 132

Concentration of insaponifiable:

0,1 - 1%

Concentration of indicated alkaline solution for saponification:

8 to 15 °Be;

The soda soap is white, hard and presents a fine and compact structure. Well soluble in water, it produces quickly an abundant stable foam, has a good washing power and produces a smooth effect on the skin.

Preparation of soap

If necessary, washing in boiling water can be used as method of purification of fat (pork).


The soapmaking characteristics of fat are similar to those of tallow. As such, saponification should be done with light alkaline solutions.

The semi-hot process is well indicated as a technique of saponification.


100 Kg of purified fat;
68,80 Kg of caustic soda at 8 °Be;
30,35 Kg of caustic soda solution at 35 °Be.


How to conduct the operations:

- Weigh the quantity of fat and heat it in the boiler at about 55 - 60 °C;
- Stop the heating and add slowly and in small proportions the low concentration alkaline solution by stirring well (appearance of an emulsion);
- Then add progressively the strong alkaline solution by stirring (increasing temperature shows good saponification process);
- Let the temperature decrease progressively down to 50 °C and add the secondary products;
- Pour the soap into moulds;
- Leave it become cold and hard;
- Take out of the moulds and cut the blocks into bars (and eventually into pieces).