What is "butyric acid"

Butyric \Bu*tyr"ic\, a. (Chem.) Pertaining to, or derived from, butter.

Butyric acid, C3H7.CO2H, an acid found in butter; an oily, limpid fluid, having the smell of rancid butter, and an acrid taste, with a sweetish aftertaste, like that of ether. There are two metameric butyric acids, called in distinction the normal- and iso-butyric acid. The normal butyric acid is the one common in rancid butter.

n. 1 (context organic compound English) Either of the two isomeric carboxylic acids, normal butyric acid and isobutyric acid, with the chemical formula C₃H₇COOH, occurring in animal milk fat. 2 (context fatty acid English) Solely the straight chain isomer of the above, normal butyric acid or n-butyric acid, CH₃(CH₂)₂COOH, a short chain fatty acid; its glyceride is one of the principle components of the flavour of butter.

n. an unpleasant smelling fatty acid found especially in butter [syn: butanoic acid]

Butyric acid (from Greek βούτῡρον, meaning "butter"), also known under the systematic name butanoic acid, abbreviated BTA, is a carboxylic acid with the structural formula C HCHCH- COOH. Salts and esters of butyric acid are known as butyrates or butanoates. Butyric acid is found in milk, especially goat, sheep and buffalo milk, butter, parmesan cheese, and as a product of anaerobic fermentation (including in the colon and as body odor). It has an unpleasant smell and acrid taste, with a sweetish aftertaste similar to ether. It can be detected by mammals with good scent detection abilities such as dogs at 10 parts per billion, whereas humans can detect it in concentrations above 10 parts per million.

Butyric acid is present in, and is the main distinctive smell of, human vomit. It is also found in milk chocolate produced by the Hershey process, or added to imitate the flavour of Hershey's chocolate.

Butyric acid was first observed in impure form in 1814 by the French chemist Michel Eugène Chevreul. By 1818, he had purified it sufficiently to characterize it. However, Chevreul did not publish his early research on butyric acid; instead, he deposited his findings in manuscript form with the secretary of the Academy of Sciences in Paris, France. Henri Braconnot, a French chemist, was also researching the composition of butter and was publishing his findings, and this led to disputes about priority. As early as 1815, Chevreul claimed that he had found the substance responsible for the smell of butter. By 1817, he published some of his findings regarding the properties of butyric acid and named it. However, it was not until 1823 that he presented the properties of butyric acid in detail. The name of butyric acid comes from the Latin word for butter, butyrum (or buturum), the substance in which butyric acid was first found.