Description
Acetobacter bacteria oxidize ethanol into acetic acid under aerobic conditions, creating sour liquid with 4-8% acidity.
Technical
A two-step biochemical process: 1) Ethanol dehydrogenase converts ethanol to acetaldehyde, 2) Aldehyde dehydrogenase oxidizes acetaldehyde to acetic acid. Requires oxygen as terminal electron acceptor (Krebs cycle). Polyphenols from raw materials undergo oxidative polymerization.
Culinary Significance
Provides acidity without citrus limitations, creates flavor complexity through esterification, and enables long-term preservation. Critical for balancing fat-rich dishes and pickling.
Science
Primary Reaction
Oxidation of ethanol to acetic acid
Parameters
Temperature
25°C optimal
18°C to 32°C range
Thermophilic strains (A. tropicalis) can operate up to 40°C
Time
2-3 months
3 weeks – 12 months
Orleans method takes 3 months vs. submerged culture (3 weeks)
Equipment