ISOVALERIC ACID

ISOVALERIC ACID

CAS NO.:  503-74-2
EC/LIST .: 207-975-3

Isovaleric acid  also known as β-methylbutyric acid or more commonly isovaleric acid, is a branched-chain alkyl carboxylic acid with the chemical formula (CH3)2CHCH2CO2H. 
Isovaleric acid is classified as a short-chain fatty acid. Like other low-molecular-weight carboxylic acids, Isovaleric acid has an unpleasant odor. 
The compound occurs naturally and can be found in many foods, such as cheese, soy milk, and apple juice.

Isovaleric acid is a C5, branched-chain saturated fatty acid. 
Isovaleric acid has a role as a plant metabolite and a mammalian metabolite. 
Isovaleric acid is a short-chain fatty acid, a methylbutyric acid and a branched-chain saturated fatty acid. 
Isovaleric acid is a conjugate acid of an isovalerate.

Isopentanoic acid is a colorless liquid with a penetrating odor. 
Isovaleric acid is slightly soluble in water.
Isovaleric acid is corrosive to metals and to tissue.

Isovaleric acid, is a natural fatty acid found in a wide variety of plants and essential oils. 
Isovaleric acid is clear colorless liquid that is sparingly soluble in water, but well soluble in most common organic solvents. 
Isovaleric acid has been suggested that isovaleric acid from pilot whales, a species frequently consumed in the Faroe Islands, may be the unusual dietary factor in prolonged gestation in the population of the Faroe Islands. 
Previous studies suggested that was due to the high intake of n-3 polyunsaturated fatty acids has been, but fatty acid data for eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA) in blood lipids of Faroese and Norwegians was reviewed in terms of the type of fish eaten (mostly lean white fish with DHA much greater than EPA); the popular lean fish, thus, probably provides too little EPA to produce a marked effect on human biochemistry (PMID 2646392 ). 
Isovaleric acid is found to be associated with isovaleric acidemia, which is an inborn error of metabolism.

Isovaleric acid, also known as isovalerate or delphinic acid, belongs to the class of organic compounds known as methyl-branched fatty acids. 
These are fatty acids with an acyl chain that has a methyl branch. 
Usually, they are saturated and contain only one or more methyl group. 
However, branches other than methyl may be present. 
Based on a literature review a significant number of articles have been published on Isovaleric acid.

Isovaleric Acid, also known as 3-methylbutanoic acid, 1-pentanoic acid, or delphinic acid, is a natural fatty acid found in many plants, essential oils, old hops, foot sweat, and some cheese. 
Isovaleric acid is characterized by a pungent aroma often described as cheesy (especially referring to aged hard cheeses) or “gym socks.” 
In beer, the flavor threshold of isovaleric acid is in the wide range of 0.1–1.5 mg/l, varying with the taster’s sensitivity. 
Isovaleric acid is a product of the oxidation of hop resins and is often quite pronounced in hops that have been exposed to oxygen over a long period of time. 
Isovaleric acid is also a by-product of contamination by, or fermentation with, Brettanomyces yeasts. 
See brettanomyces. 
The presence of isovaleric acid in beer is usually considered a flaw, but it is considered appropriate as a background note in some English-style ales and can be stronger in beers purposely fermented with Brettanomyces. 
Excessive isovaleric acid in beer is best prevented by appropriate hop storage and clean brewing practices to prevent wild yeast infections. 
Because oxygen is the catalyst that forms isovaleric acid in hops, all hops should be stored cold and tightly packed to limit their exposure to the air.

Melting point:-29 °C (lit.)
Boiling point:175-177 °C (lit.)
Density 0.925 g/mL at 20 °C (lit.)
vapor pressure 0.38 mm Hg ( 20 °C)
refractive index n20/D 1.403(lit.)
FEMA 3102 | ISOVALERIC ACID
Flash point:159 °F
storage temp. Store below +30°C.
solubility 48g/l
form Liquid
pka4.77(at 25℃)
color Clear colorless to slightly yellow
Specific Gravity0.928 (20/20℃)
PH3.1 (10g/l, H2O, 25℃)
explosive limit1.5-6.8%(V)
Water Solubility 25 g/L (20 ºC)
Merck 14,5231
JECFA Number259
BRN 1098522

Isovaleric acid is a minor constituent of the perennial flowering plant valerian (Valeriana officinalis), from which it got its trivial name isovaleric acid: an isomer of valeric acid which shares its unpleasant odor.
The dried root of this plant has been used medicinally since antiquity. 
Their chemical identity was first investigated in the 19th century by oxidation of the components of fusel alcohol, which includes the five-carbon amyl alcohols. 

Isovaleric acid is a synonym of the 3-methylbutanoic acid. 
Isovaleric acid is also so called as the isomer of valeric acid.

Isovaleric acid has a strong pungent cheesy or sweaty smell, but its volatile esters I low concentrations have pleasing scents and are used widely as fruity flavor and as essence in the perfumery industry. 
Olfactory detection is at very low concentration and is considered as malodorous substances based on the Offensive Odor Control Act.

“Odor intensity” between 2.5 to 3.5 with an olfactory noticing concentration of 0.001 to 0.01ppm.

Isovaleric acid can be olfactory detected in concentration between 0.001 to 0.00005ppm.

Isovaleric acid’s odor is an offensive odor having an unpleasantness similar to cheese, sweat, feet, or foul breathe due to old age.

Isovaleric acid is also a causative agent for feet odors.

Isovaleric acid is poor water-soluble compound at 2.4g/100ml level. 
Isovaleric acid is the lowest molecular weight carboxylic acid that dissolves better in non-polar solvents rather than polar solvents.

Isovaleric acid has a strong pungent cheesy or sweaty smell, but its volatile esters such as ethyl isovalerate have pleasant odors and are widely used in perfumery. 
Isovaleric acid is also the primary flavor added to wine when made using Brettanomyces yeasts.
Other compounds produced by Brettanomyces yeasts include 4-ethylphenol, 4-vinylphenol, and 4-ethylguaiacol.
An excess of isovaleric acid in wine is generally seen as a defect, as it can smell sweaty, leathery, or "like a barnyard", but in small amounts it can smell smokey, spicy, or medicinal.
These phenomena may be prevented by killing any Brettanomyces yeasts, such as by sterile filtration, by the addition of relatively large quantities of sulfur dioxide and sometimes sorbic acid, by mixing in alcoholic spirit to give a fortified wine of sufficient strength to kill all yeast and bacteria, or by pasteurization. 
Isovaleric acid can also be found in beer, and, excepting some English–style ales, is usually considered a flaw.
Isovaleric acid can be produced by the oxidation of hop resins, or by Brettanomyces yeasts present. 

The compound's safety as a food additive was reviewed by an FAO and WHO panel, who concluded that there were no concerns at the likely levels of intake.

IUPAC NAME :

3-Methylbutanoic acid
 
3-methylbutanoic acid
 
3-Methylbutyric acid
 
3-METHYLBUTYRIC ACID
 
Isovaleric Acid
 
Isovaleric acid
 
isovaleric acid
 
Isovaleric acid
 

SYNONYMS:

1098522 [Beilstein]
207-975-3 [EINECS]
3-Methylbutanoic acid [ACD/IUPAC Name] [Wiki]
3-Methylbutansäure [German] [ACD/IUPAC Name]
3-Methylbutyric Acid
3-Methyl-n-butyric acid
503-74-2 [RN]
Acide 3-méthylbutanoïque [French] [ACD/IUPAC Name]
Butanoic acid, 3-methyl- [ACD/Index Name]
Isovaleric acid