A fatty acid is a carboxylic acid (or organic acid), often with a long aliphatic tail (long chains), either saturated or unsaturated. Most natural fatty acids have an even number of carbon atoms, because they are made up of acetate that has two carbon atoms. Fatty acids vary in length and degree of saturation and are generally up to 26 carbons long. They are the sub-units that, along with glycerol, form the basic unit of fat, the triglyceride. Fatty acids can be saturated, polyunsaturated or monounsaturated. Saturated fatty acids include acetic, butyric and palmitic acids). Polyunsaturated fatty acids include linoleic, linolenic and arachidonic acids. Oleic acid is an example of a monounsaturated fatty acid.
Fatty acids are typically found in plant and animal lipids (fat), such as glycerides, sterols, and phospholipids. They occur naturally in waxes, fats and essential oils. Fatty acids are used in cosmetics as emollients, thickening agents and when mixed with glycerin, cleansing agents. They are used in cooking and food engineering and in the production of soaps, detergents, and cosmetics and are a component of some low toxicity pesticides.
Fatty acids are the basic building blocks for all lipids and are a component of phospholipids and fats. They are required in the body for cell membrane function and integrity, healthy skin, cholesterol metabolism, and prostaglandin production.
They help maintain resilience and lubrication of all cells, and combine with protein and cholesterol to form living membranes that hold body cells together. They break up cholesterol deposits on arterial walls, thereby preventing arteriosclerosis. Fatty acids are necessary for the function of the thyroid and adrenal glands.
Esters are substances that have the functional group (R-COO-R\') (the carbon is double-bonded to one oxygen atom and single-bonded to another) and consist of an alkane covalently bonded with the residue of any oxygen acid, organic or inorganic. An ester is a product of the reaction of an acid (usually organic) and an alcohol (the hydrogen of the acid R-COOH is replaced by an alkyl group R\").
Esters are responsible for many fruity flavors, aromas and floral scents including the principal odor in ripe bananas (amyl acetate) as well as those in beer and wine. They are formed from alcohols by the action of yeast.
- cottonseed oil
Cottonseed oil, derived from the seeds of the cotton plant, contains fatty acids and is used in soaps and margarine. It is most often measured using HPLC, GC/FID and GC/MS.
- linseed oil
Linseed oil is an oil derived from the flax plant, whose chief constituents are glycerides of linolenic, oleic, linoleic and saturated fatty acids. It is most often measured using HPLC, GC/FID and GC/MS.
- palmitic acid
Palmitic acid is a naturally occurring fatty acid also produced commercially from palm and coconut oil. It is used is soaps, cosmetics and food additives. It is most often measured using HPLC, GC/FID and GC/MS.
- stearic acid
Stearic acid, prepared by hydrogenation of cottonseed oil, is used in manufacturing soaps and greases. It is most often measured using HPLC, GC/FID and GC/MS.