Components of fats and oils, which are used in making soap, fatty acids are weak acids that are composed of two parts -
- A carboxylic acid group
- Hydrocarbon chain
Fats are esters in which the OR' (alcohol) part of the molecule is the trihydroxy compound, glycerol (HOCH2CHOHCH2OH). As each glycerol molecule can be esterified with a different carboxylic acid, there are three carboxylic acid portions in these molecules, which are consequently known as triacylglycerols or triglycerides. These carboxylic acid groups generally have long hydrocarbon chains of 14-20 carbons (including the carbonyl carbon). These chains are usually unbranched and, most importantly, they contain even numbers of carbon atoms. The carboxylic acids that are obtained by hydrolysis of fats are known as fatty acids.
This is interpreted to determine that the fatty acids are made up of 2-carbon atoms at a time. Each unit of 2-carbon atoms is added by reacting the alpha carbon of one acetate unit with the carbonyl carbon of the next.
Fats for Soapmaking
It has been found that almost any fat can be used in soapmaking. Fats for soap making may include animal fats, like tallow (fat from beef), lard (fat from pork), and many plants derived hydrogenated fats and oils. Traditionally, animal fats have been used, with beef tallow considered to make the hardest soap, pork lards - medium hardness soap and chicken fat as the softest. Now days, it is generally accepted that the harder fats produce better soap.
There are variety of fats with each bring their own unique characteristics and qualities to soap. Whatever type of fat or oil is used, it is important to make sure that it is clean and free of impurities. It should not be rancid, should have excess salt in it, or have any solid particles. Rancid and dirty fat can be cleaned by heating it for a few minutes in a large container, with four parts water to one part fat. Set it aside and let it to cool down. After the fat has solidified, remove it from the container in one piece.
Best Soaps for Skincare
According to experts, lard beats tallow and vegetable oils have found to be highly gentle and great for skin. However, soaps made with 100% lard do not lather very well but they are known to have effective in cleaning. There is a predominant perception today that you should get bubbles for the soap for its proper functioning.