Genus/species: Acetobacter estuniensis
Gram Stain: Negative
Morphology:
- Cell: ellipsoid or rod-shaped
- Colony:
- Liquid Growth: dispersed
Physiological Traits:
Carbon sources are glucose, ethanol, mannitol; produce acetic acid; requires oxygen for growth but may be able to use other reducible compound as electron acceptors to survive partial anaerobiosis; organic acids may be possible oxidation substrates.
Ecological Traits:
A. estuniensis has been found in apple cider, may be found in other naturally fermented food products, has been isolated from wine on occasion but is a rare wine contaminant.
Distinguishing Features:
Electrophoretic analysis for identification of A. estuniensis requires treatment with 3 endonucleases to ultimately distinguish it from A. aceti.
Role in wine:
May inhibit yeast fermentation if prolific in must; generate acetic acid (volatile acidity) in presence of oxygen, thereby spoiling wine; possibility of using organic acids as oxidation substrate may reduce overall organic acid concentration; potential acetaldehyde production binds SO2
Sensitivities:
- SO2: Sensitive
- Sorbate:
- DMDC:
- pH: Sensitive to low pH
- Acids:
- Ethanol:
- Anaerobiosis: no growth
- Heat: Sensitive to cold temperatures