In the generator method of ethanoic acid fermentation, Acetobacter aceti are grown over wood shavings in a fermenter to the point where they form a biofilm. At the base of the fermenter oxygen is bubbled in, which then rises through the wood shavings. Ethanol drips through the wood shavings. At a suitable temperature the ethanol is converted to ethanoic acid, which is withdrawn from the bottom of the fermenter, and new ethanol is added at the top.
List two abiotic variables that would need to be monitored during this fermentation process.
a. oxygen ✓ b. temperature ✓ c. pH levels ✓ d. CO₂ ✓
Describe one way in which microorganisms in this fermenter could be limited by their own activities.
a. name of a factor ✓ b. description ✓
eg a. pH b. lowered by «ethanoic» acid production.
eg a. increase in temperature b. due to metabolism.
eg a. increased population size/reproduction b. would limit resources.
eg a. increased metabolic waste b. causes toxic environment.
