Alcoholic Fermentation
Detailed mechanism of alcoholic fermentation, including the organisms involved and the production of ethanol and carbon dioxide.
What is Alcoholic Fermentation?
An anaerobic metabolic process that converts sugar to acids, gases, or alcohol.
Key formula / rule: Overall Reaction of Alcoholic Fermentation
Key points
- Describe the steps of alcoholic fermentation.
- Identify the organisms that perform alcoholic fermentation.
- Explain the role of pyruvate, acetaldehyde, ethanol, CO2, NAD+, and NADH.
- Understand the significance of NAD+ regeneration.
Common exam trap
Confusing alcoholic fermentation with lactic acid fermentation.
Definitions
- Term
Fermentation
- Meaning
An anaerobic metabolic process that converts sugar to acids, gases, or alcohol.
- Term
Acetaldehyde
- Meaning
A volatile, pungent liquid aldehyde, an intermediate in alcoholic fermentation.
- Term
Pyruvate Decarboxylase
- Meaning
An enzyme that catalyzes the decarboxylation of pyruvate to acetaldehyde.
- Term
Alcohol Dehydrogenase
- Meaning
An enzyme that catalyzes the reduction of acetaldehyde to ethanol, using NADH.
Learning objectives
Describe the steps of alcoholic fermentation.
Identify the organisms that perform alcoholic fermentation.
Explain the role of pyruvate, acetaldehyde, ethanol, CO2, NAD+, and NADH.
Understand the significance of NAD+ regeneration.
Differentiate alcoholic fermentation from other metabolic pathways.
Formulae
- Name
Overall Reaction of Alcoholic Fermentation
- Note
This represents the net conversion from glucose, encompassing glycolysis and the subsequent fermentation steps.
- Expression
C6H12O6 (Glucose) → 2 C2H5OH (Ethanol) + 2 CO2 (Carbon Dioxide)
Prerequisites
Glycolysis
Cellular Respiration
Enzymes
Anaerobic conditions
Common mistakes
Confusing alcoholic fermentation with lactic acid fermentation.
Forgetting that glycolysis precedes fermentation.
Not understanding the role of NAD+ regeneration.
Assuming fermentation produces significant ATP directly.
Keywords
Alcoholic Fermentation
Yeast
Ethanol
Carbon Dioxide
Pyruvate
Acetaldehyde
NAD+
NADH
Anaerobic Respiration
Glycolysis
Saccharomyces cerevisiae
Practice preview
What is the correct sequence of intermediate compounds and enzymes involved in alcoholic fermentation starting from pyruvic acid?…
medium
Which of the following organisms primarily carries out alcoholic fermentation?…
easy
What is the crucial role of fermentation in anaerobic conditions for glycolysis to continue?…
easy