Acetoin

• Acetoin
• Acetylmethylcarbinol
• 2-butanol -3-one
• 3- hydroxybutan -2-one
• Dimethylketol
• 1- Acetylethanol
• (1- hydroxyethyl)- methyl ketone
• 2,3- Butanolon

Colorless, pleasant -smelling liquid

Liquid

1.01 g · cm -3 ( 25 ° C)

15 ° C.

147 ° C

5 hPa (20 ° C)

• Moderately in water (100 g · l-1 at 20 ° C)
• Miscible with ethanol

Attention

Template: Infobox chemical / molecular formula search available

3-hydroxy -2-butanone or acetoin is an organic compound which is formed by some bacteria as intermediate metabolism, but is also found in parts of plants. This formed the (R )-isomer.

Occurrence

Known bacterial Acetoinbildner are, for example, in the genus Bacillus, found among the Enterobacteriaceae and lactic acid bacteria. Acetoin is produced during the anaerobic breakdown of glucose, but only in certain fermentation processes accumulated ( 2.3 - Butandiolgärung ). Under aerobic conditions, the connection is completely broken down to carbon dioxide ( for example, in mammals ).

The ability to Acetoinbildung is used for screening test method for the determination of unknown ( intestinal ) bacteria. The reaction with α -naphthol leads in this case to form a red dye ( Voges - Proskauer test, IMViC ).

Production

Acetoin may be obtained by reduction of 2,3-butanedione or by enzymatic digestion of carbohydrates with Bacillus tartaricus acetaldehyde.

Properties

Acetoin has a butter-like smell and is used for the production of flavorings. In addition, there is a natural component among others of apples, butter, yogurt, asparagus, black currants, blackberry, wheat, broccoli, Brussels sprouts, and melons. Due to its α - hydroxyketone structure it has a reducing effect, wherein it is oxidized to 2,3-butanedione ( diacetyl ).

Use

The connection is among the additives that cigarette manufacturers add tobacco.