| Oenococcus oeni | |
|---|---|
| Scientific classification | |
| Kingdom: | Bacteria |
| Division: | Firmicutes |
| Class: | Bacilli |
| Order: | Lactobacillales |
| Family: | Leuconostocaceae |
| Genus: | Oenococcus (Garvie 1967) Dicks et al. 1995 |
| Species: | O. oeni |
| Binomial name | |
| Oenococcus oeni |
|
| Synonyms | |
|
Leuconostoc oeni |
|
Oenococcus oeni is a Gram-positive bacteria species in the genus of Oenococcus. It used to be the only species in the genus (which was known as Leuconostoc oeni until 1995). In 2006, the species Oenococcus kitaharae was identified. As its name implies, Oenococcus oeni holds major importance in the field of oenology, where it is the primary bacteria involved in completing the malolactic fermentation[1].
Diacetyl in wine is produced by lactic acid bacteria, mainly O. oeni. In low levels it can impart positive nutty or caramel characters, however at levels above 5 mg/L it creates an intense buttery or butterscotch flavour, where it is perceived as a flaw. The sensory threshold for the compound can vary depending on the levels of certain wine components, such as sulfur dioxide. It can be produced as a metabolite of citric acid when all of the malic acid has been consumed. Diacetyl rarely taints wine to levels where it becomes undrinkable[2].