97%

Synonyms: Biacetyl, Diacetyl

Linear Formula: CH3COCOCH3

CAS Number: 431-03-8

Molecular Weight: 86.09

EC Number: 207-069-8

MDL number: MFCD00008756

Diacetyl is a yellow-green liquid with a strong, greasy smell of butter and sour cream, but is practically tasteless. Soluble in water 25%. Forms an azeotrope with methanol (+62°C, 25%). Highly volatile.

Diacetyl and acetoin are two compounds that give butter its characteristic taste. Because of this, manufacturers of artificial butter flavoring, margarines or similar oil-based products typically add diacetyl and acetoin (along with beta-carotene for the yellow color) to make the final product butter-flavored.