Caprylic acid (from the Latin word capra, meaning "goat"), also known under the systematic name octanoic acid, is a saturated fatty acid and carboxylic acid with the structural formula CH3(CH2)6CO2H. It is a colorless oily liquid that is minimally soluble in water with a slightly unpleasant rancid-like smell and taste. Salts and esters of octanoic acid are known as octanoates or caprylates. It is a common industrial chemical, which is produced by oxidation of the C8 aldehyde. Its compounds are found naturally in the milk of various mammals and as a minor constituent of coconut oil and palm kernel oil.
|Preferred IUPAC name
C8:0 (Lipid numbers)
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||144.214 g·mol−1|
|Appearance||Oily colorless liquid|
|Odor||Faint, fruity-acid; irritating|
|Melting point||16.7 °C (62.1 °F; 289.8 K)|
|Boiling point||239.7 °C (463.5 °F; 512.8 K)|
|0.068 g/100 mL|
|Solubility||soluble in alcohol, chloroform, ether, CS2, petroleum ether, acetonitrile|
|Vapor pressure||0.25 Pa|
1.055 (2.06–2.63 K)
Refractive index (nD)
Heat capacity (C)
|297.9 J/K mol|
Std enthalpy of
|NFPA 704 (fire diamond)|
|Flash point||130 °C (266 °F; 403 K)|
|440 °C (824 °F; 713 K)|
|Lethal dose or concentration (LD, LC):|
LD50 (median dose)
|10.08 g/kg (orally in rats)|
|Heptanoic acid, Nonanoic acid|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Caprylic acid is used commercially in the production of esters used in perfumery and also in the manufacture of dyes.
Caprylic acid is an antimicrobial pesticide used as a food contact surface sanitizer in commercial food handling establishments on dairy equipment, food processing equipment, breweries, wineries, and beverage processing plants. It is also used as disinfectant in health care facilities, schools/colleges, animal care/veterinary facilities, industrial facilities, office buildings, recreational facilities, retail and wholesale establishments, livestock premises, restaurants, and hotels/motels. In addition, caprylic acid is used as an algicide, bactericide, fungicide, and herbicide in nurseries, greenhouses, garden centers, and interiors, and on ornamentation. Products containing caprylic acid are formulated as soluble concentrate/liquids and ready-to-use liquids.
Caprylic acid plays an important role in the body's regulation of energy input and output, a function which is performed by the hormone ghrelin. The sensation of hunger is a signal that the body requires an input of energy in the form of food consumption. Ghrelin stimulates hunger by triggering receptors in the hypothalamus. In order to activate these receptors, ghrelin must undergo a process called acylation in which it acquires an -OH group, and caprylic acid provides this by linking at a specific site on ghrelin molecules. Other fatty acids in the same position have similar effects on hunger.
Some studies have shown that medium-chain triglycerides (MCTs) can help in the process of excess calorie burning, and thus weight loss; however, a systematic review of the evidence concluded that the overall results are inconclusive. Also, interest in MCTs has been shown by endurance athletes and the bodybuilding community, but MCTs have not been found to be beneficial to improved exercise performance.
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