The soap making information can tell a lot about the ingredients and the different ways to manufacture soap. It is a well-known fact that oils and fats used in soap-making are compounds of glycerin and a fatty acid. When oils are mixed with an alkali, they form glycerin and the sodium salt of the fatty acid. It is a must to make sure that the quality of raw materials is high, since the raw materials to a large extent predetermine the quality of soap. For soap making, the required fatty acids come from the tallow, grease, fish oils, and vegetable oils. So, the hardness, lathering qualities, and transparency of soap vary according to the combinations of fats and alkalis used as ingredients.
The different kinds of soap include medical soap, soap for shaving, liquid soap, technical soap, etc. The technical soap is manufactured in the following way. Animal fat, as already mentioned, is liquated and mixed with dissolved caustic sodium. This mixture is further exposed to hashing. The homogeneous mass is then poured into containers and is kept in a warm and dry place for about four or five days. When soap gets hardened, it can be cut into small pieces or melted.
Other kinds of soap, such as toilet or medical soap, go through the soap purification processes. Soap can be purified using two methods: mechanical and chemical. Preference is given to neither, since they both are highly effective.
The soap making information tells us that one of the most popular kinds of soap is medical soap. It possesses strong bactericidal and anti-inflammatory properties. The ingredients used to produce such soap include menthol, camphor, carbolic acid, and formalin.
As already mentioned in the soap making information, vegetable oils are extensively used in the soap-making process, along with animal fats. Most frequently used vegetable oils include palm oil and coconut oil. The coconut oil has a softening and moisturizing effect on the skin - that is why it is so popular. However, an experienced soap crafter would normally use many combinations of oils.
The soap making information also contains data on the perfumery added to soaps. Most frequently used aromas are of citrus, bergamot, anise, apples, and cinnamon. Adding fragrances to soap, manufacturers have to carefully test all aromatic components to find out whether they contain any allergens. If the soap is intended for use by infants, all hypoallergic soap aromatic components have to be excluded.
We have largely investigated the physics of soap-making processes. Chemistry can provide a no less interesting soap-making information. As we know, most soaps remove grease and dirt because some of their components are surfactants (surface-active agents). Surfactants have a molecular structure that acts as a link between water and the dirt particles. This loosens the particles from the underlying fibers or surfaces to be cleaned. One end of the molecule is hydrophilic (attracted to water), and the other is hydrophobic (attracted to substances that are not water soluble). This peculiar structure allows soap to adhere to substances that are otherwise insoluble in water, while the dirt is then washed away with the soap.