methyl 2-(methyl thio) butyrate

Methyl 2-(methyl thio) butyrate, also known by its trivial name methyl 2-methylsulfanylbutanoate, is a sulfur-containing organic ester with the molecular formula C₆H₁₂O S. This compound features a characteristic sulfurous odor profile that is musty, onion-like, fruity, tropical, and green. It belongs to the class of flavoring esters and has multiple synonyms reflecting its chemical structure, including methyl 2-(methylmercapto)butyrate. According to PubChem, it is a specialized flavor compound commonly sourced from natural origins such as beer and hop oil. These natural matrices provide this ester in trace amounts contributing to complex aroma profiles. It finds utility primarily in flavoring applications where sulfur notes are desirable.

Methyl 2-(methyl thio) butyrate occurs naturally in biological sources like beer and hop oil, where it contributes to complex sulfurous and fruity aroma characteristics. Its presence in such matrices suggests a role in imparting flavor nuances typical to fermented beverages and certain botanical extracts. This compound is applied as a flavoring agent in various foodstuffs including dairy products, garlic, mango, milk, onion, and pineapple flavors. The compound's use levels and safety evaluations align with the guidelines of FEMA (US) which designate it under flavoring agent standards. Such regulatory frameworks support its controlled incorporation to enhance sensory profiles in formulated products.

Methyl 2-(methyl thio) butyrate is a sulfur-containing ester with moderate molecular weight and a characteristic molecular formula C₆H₁₂O S. It exhibits a boiling point range between 149 and 151 °C at standard atmospheric pressure (760 mm Hg), making it moderately volatile. The compound's specific gravity measured at 25 °C ranges from 0.944 to 0.952, indicating a density slightly less than water. Its refractive index at 20 °C lies between 1.457 and 1.463, which informs optical properties relevant to formulation. With an estimated octanol-water partition coefficient (log P) of 1.70, the compound has moderate lipophilicity, affecting solubility and miscibility. Vapor pressure at 25 °C is around 1.112 mmHg, reflecting moderate volatility. Its flash point is approximately 33 °C (91 °F), requiring careful handling due to flammability. Solubility profiles indicate it is soluble in alcohol and slightly soluble in water (estimated 5239 mg/L at 25 °C). These physicochemical parameters influence its behavior in flavor matrices and dictate appropriate formulation conditions.

(IUPAC):	Atomic Weights of the Elements 2011 (pdf)
Videos:	The Periodic Table of Videos
tgsc:	Atomic Weights use for this web site
(IUPAC):	Periodic Table of the Elements
HMDB (The Human Metabolome Database):	HMDB41306
FooDB:	FDB021225
Export Tariff Code:	2930.90.9999
VCF-Online:	VCF Volatile Compounds in Food
ChemSpider:	View

Safety information

Preferred SDS: View
European information :
Most important hazard(s):
Xi - Irritant
R 10 - Flammable. R 36/37/38 - Irritating to eyes, respiratory system, and skin. S 02 - Keep out of the reach of children. S 26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S 36/37/39 - Wear suitable clothing, gloves and eye/face protection.
Hazards identification
Classification of the substance or mixture
GHS Classification in accordance with 29 CFR 1910 (OSHA HCS)
None found.
GHS Label elements, including precautionary statements
Pictogram
Hazard statement(s)
None found.
Precautionary statement(s)
None found.
Oral/Parenteral Toxicity:
gavage-rat LD50 [sex: M,F] 2108 mg/kg (Piccirillo & Lunchicki, 1982)
Dermal Toxicity:
Not determined
Inhalation Toxicity:
Not determined

Safety in use information

Category:
flavoring agents
Recommendation for methyl 2-(methyl thio) butyrate usage levels up to:
	not for fragrance use.
Maximised Survey-derived Daily Intakes (MSDI-EU):		0.097 (μg/capita/day)
Structure Class:		II
Use levels for FEMA GRAS flavoring substances on which the FEMA Expert Panel based its judgments that the substances are generally recognized as safe (GRAS).
The Expert Panel also publishes separate extensive reviews of scientific information on all FEMA GRAS flavoring substances and can be found at FEMA Flavor Ingredient Library
publication number: 13
Click here to view publication 13
		average usual ppm	average maximum ppm
baked goods:		-	-
beverages(nonalcoholic):		-	-
beverages(alcoholic):		-	0.50000
breakfast cereal:		-	-
cheese:		-	-
chewing gum:		-	-
condiments / relishes:		-	-
confectionery froastings:		-	0.30000
egg products:		-	-
fats / oils:		-	-
fish products:		-	-
frozen dairy:		-	0.30000
fruit ices:		-	-
gelatins / puddings:		-	0.50000
granulated sugar:		-	-
gravies:		-	-
hard candy:		-	0.50000
imitation dairy:		-	0.30000
instant coffee / tea:		-	-
jams / jellies:		-	-
meat products:		-	-
milk products:		-	-
nut products:		-	-
other grains:		-	-
poultry:		-	-
processed fruits:		-	-
processed vegetables:		-	-
reconstituted vegetables:		-	-
seasonings / flavors:		-	-
snack foods:		-	-
soft candy:		-	0.30000
soups:		-	-
sugar substitutes:		-	-
sweet sauces:		-	-

Safety references

European Food Safety Athority(EFSA):Flavor usage levels; Subacute, Subchronic, Chronic and Carcinogenicity Studies; Developmental / Reproductive Toxicity Studies; Genotoxicity Studies...

European Food Safety Authority (EFSA) reference(s):

Flavouring Group Evaluation 8 (FGE.08)[1]: Aliphatic and alicyclic mono-, di-, tri-, and polysulphides with or without additional oxygenated functional groups from chemical group 20 View page or View pdf

Flavouring Group Evaluation 8, Revision 1 (FGE.08Rev1): Aliphatic and alicyclic mono-, di-, tri-, and polysulphides with or without additional oxygenated functional groups from chemical groups 20 and 30 View page or View pdf

Scientific Opinion on Flavouring Group Evaluation 8, Revision 3 (FGE.08Rev3): Aliphatic and alicyclic mono-, di-, tri-, and polysulphides with or without additional oxygenated functional groups from chemical groups 20 and 30 View page or View pdf

Scientific Opinion on Flavouring Group Evaluation 08, Revision 4 (FGE.08Rev4): Aliphatic and alicyclic mono-, di-, tri-, and polysulphides with or without additional oxygenated functional groups from chemical groups 20 and 30 View page or View pdf

EPI System: View

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Toxicology Citations:Search

EPA ACToR:Toxicology Data

EPA Substance Registry Services (SRS):Registry

Laboratory Chemical Safety Summary :560572

National Institute of Allergy and Infectious Diseases:Data

WISER:UN 3272

WGK Germany:3

methyl 2-methylsulfanylbutanoate

Chemidplus:0051534668

methyl (2R)-2-methylsulfanylbutanoate

methyl (2S)-2-methylsulfanylbutanoate