Stearic acid

Stearic Acid

Structural formula of stearic acid

Stearic acid is a saturated fatty acid with an 18-carbon chain. It is one of the most common saturated fatty acids found in nature following palmitic acid. Its IUPAC name is octadecanoic acid. Stearic acid is a waxy solid and its chemical formula is C__H__O_.

Occurrence

Stearic acid is found in various animal and plant fats. It is a major component of cocoa butter and shea butter. In animal fats, it is typically present as a triglyceride, which is a type of lipid molecule.

Production

Stearic acid is produced by the hydrogenation of unsaturated fatty acids derived from animal and vegetable fats and oils. The process involves the addition of hydrogen to the double bonds of unsaturated fatty acids, converting them into saturated fatty acids.

Uses

Stearic acid is used in the production of soaps, cosmetics, detergents, and candles. It is also used as a hardening agent in the manufacture of rubber and plastics. In the pharmaceutical industry, stearic acid is used as an excipient in the production of tablets and capsules.

Health Effects

Stearic acid is considered to have a neutral effect on cholesterol levels in the blood. Unlike other saturated fatty acids, it does not appear to raise LDL cholesterol levels. It is metabolized in the body to oleic acid, a monounsaturated fatty acid.

Chemical Properties

Stearic acid is insoluble in water but soluble in ethanol and other organic solvents. It has a melting point of about 69.3 °C (156.7 °F) and a boiling point of 361 °C (682 °F). The acid is known for its ability to form a stable emulsion and is often used in the production of emulsifiers.

Related Pages

• Fatty acid
• Saturated fat
• Triglyceride
• Lipid
• Hydrogenation