4-Methyloctanoic acid

Synonym(s):(R,S)-(+,-)-4-Methyloctanoic acid

CAS NO.：54947-74-9
Empirical Formula: C9H18O2
Molecular Weight: 158.24
MDL number: MFCD00051938
EINECS: 259-404-2
SAFETY DATA SHEET (SDS)
Update Date: 2026-05-28 01:12:22

What is 4-Methyloctanoic acid?

Description

4-Methyloctanoic acid, also known as Hircinoic Acid, presents as a colorless to pale-yellow oil. It is slightly soluble in chloroform, DMSO and ethyl acetate. Store in a tightly closed container in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. This substance is stable under recommended storage conditions. 4-Methyloctanoic Acid is incompatible with strong oxidizing agents as well as strong bases. This chemical causes severe skin burns and eye damage.

Chemical properties

4-Methyloctanoic acid has a fatty, musty, plastic odor. This compound is also reported to have a goat, costus, mutton odor

Physical properties

4-Methyloctanoic acid is one of the acids mainly responsible for the so-called "soo" odour of mutton. The analogue 4-Ethyloctanoic acid (found in Virginia tobacco and Costus root oil) also has a related goaty odor; this analog has the lowest threshold of all the fatty acids at 1.8 ppb. 4-Methyloctanoic acid is used in flavours for cheese, meat, tobacco and (possibly) fish. Normal use levels in finished consumer product: up to 3 ppm.

Occurrence

Reported found in cooked mutton fat, raw and cooked mutton, lamb, and blue, cheddar, parmesan, provolone and romano cheeses

The Uses of 4-Methyloctanoic acid

Hircinoic Acid, can be used as flavors and fragrance additive. It is also a building block use din sythesis of various chemical compounds such as, rac-Mono-(4-methyloctanyl)-phthalate (M566530).

Definition

ChEBI: 4-methyl-octanoic acid is a medium-chain fatty acid.

Aroma threshold values

Aroma characteristics at 1.0% in PG: waxy, fatty, meaty, reheated beef-like with a slightly lactonic cheesy nuance

Taste threshold values

Taste characteristics at 10 ppm: fatty, waxy, creamy and lactonic with a satiating fatty mouthfeel and metallic nuances.

General Description

4-Methyloctanoic acid is a branched fatty acid commonly used in the flavor and fragrance industries. This compound gives sweaty and goaty flavors to the mutton meat and goat′s milk cheese, respectively.

Biochem/physiol Actions

Taste at 10 ppm

Properties of 4-Methyloctanoic acid

Melting point:	-29.5°C (estimate)
Boiling point:	149 °C22 mm Hg(lit.)
Density	0.91 g/mL at 25 °C(lit.)
refractive index	n20/D 1.433(lit.)
FEMA	3575 \| 4-METHYLOCTANOIC ACID
Flash point:	>230 °F
storage temp.	Sealed in dry,Room Temperature
solubility	Chloroform (Slightly), DMSO (Sparingly), Ethyl Acetate (Slightly)
form	clear liquid
pka	4.78±0.10(Predicted)
color	Colorless to Light yellow to Light orange
Odor	at 10.00 % in propylene glycol. fatty waxy musty plastic dairy creamy milk
JECFA Number	271
BRN	1755426
CAS DataBase Reference	54947-74-9(CAS DataBase Reference)
NIST Chemistry Reference	4-Methyloctanoic acid(54947-74-9)
EPA Substance Registry System	4-Methyloctanoic acid (54947-74-9)

Safety information for 4-Methyloctanoic acid

Signal word	Danger
Pictogram(s)	Corrosion Corrosives GHS05
GHS Hazard Statements	H314:Skin corrosion/irritation
Precautionary Statement Codes	P280:Wear protective gloves/protective clothing/eye protection/face protection. P363:Wash contaminated clothing before reuse. P303+P361+P353:IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower. P305+P351+P338:IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing. P405:Store locked up.