Acetobacter estuniensis

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