Glycerin was discovered in 1779, by the German chemist Scheele, during the saponification of olive oil with lead oxide. In 1811, the French chemist Chevreul introduced the term ‘glycerin’, which comes from Greek (glycos = sweet). In 1836, Pelouze presented the empirical composition and, in 1872, Friedel synthesized glycerin from acetone, via isopropanol, propenol, 1,2-dichloropropane and 1,2,3-trichloropropane. Glycerin, in the form of fatty acid ester, can be found in all fats and oils, which means that it is widely distributed by nature.

Coconut and palm oils, tallow and soybean oil contain 17%, 11%, 10% and 10% glycerin, respectively, causing part of this substance to be found daily in our daily dietary intake. It also appears as lecithin in egg yolks, brain tissue, blood cells, bile and nervous system tissues. Glycerin is also formed, to a lesser extent, during alcoholic fermentation and, consequently, we find small quantities in wine.

Currently, there are four different methods that are used to obtain glycerin:

1. hydrolysis from fats (decomposition of fatty acid esters) 2. synthesis, starting with propane, 3. hydrolysis of saccharides, followed by catalytic hydrogenation (glycergen) and 4. alcoholic fermentation.

Originally, glycerin was a byproduct of fat saponification. In the year 1940, when synthetic detergents dominated the market, particularly in the US, there was not enough glycerin with a base of fatty acids to meet the demand, so synthesizing processes were developed (see above). Currently, in many countries, the production of glycerin with a petrochemical base has reached its highest level.

Glycerin is a clear liquid, almost colorless, thick, with a greasy texture. It is highly hygroscopic, miscible in water and ethanol, sparingly soluble in acetone and ether, and practically insoluble in volatile fats and oils. Glycerin is used mainly in the plastics industry (alkyd resins, polyurethane foams) and in chemical industries (quinoline, benzantrone, blue alizarin). Large amounts of glycerin are used in moisturizers (tobacco), as well as on the basis of creams (toothpastes), in skin care products (hand creams) and to sweeten beverages and extract natural substances.

Glycerin is also used for finishes in the textile industry. Other applications include: agents for heating system changers, sealing fluids, brake fluids and coolants (arctic beetles can survive temperatures up to -85 ° C, since they are able to synthesize glycerin in their blood), softeners for rubber products (tires), high pressure liquids for hydraulic systems and for the industrial manufacture of printing inks (stamp inks and printing presses, inks for photocopiers). Currently, approximately 4% of the production of glycerin is used in the manufacture of explosives (nitroglycerin).

In the pharmaceutical market, glycerin is used (rectally) as a purgative. Glycerin can not be administered parenterally or intravenously (solubilizers for medications), as this would lead to hemolysis.