Liberation of Carbon Dioxide gas during Fermentation

Our Objective

To study the liberation of carbon dioxide gas during fermentation.


The Theory

All living organisms use respiration to obtain the energy needed to run their cellular processes. The majority of animal respiration happens when there is oxygen present (aerobically). Some organisms, including bacteria, yeast, and others, can generate energy when oxygen is not present (anaerobically). 


By converting starch or sugar to alcohol or an acid anaerobically is called fermentation. The fermentation process, is a metabolic process that is enzyme-catalysed and releases energy. Zymology is the field of study of fermentation. 

Types of Fermentation

  1. Homo fermentation – Only one product is formed.
  2. Hetero fermentation – More than one product is formed.

Lactic acid Fermentation  

A metabolic process called lactic acid fermentation turns six-carbon sugars like glucose or other six-carbon sugar disaccharides like sucrose or lactose into the metabolite lactate and cellular energy, which is lactic acid in solution. 

Alcoholic Fermentation 

Alcoholic fermentation is a sophisticated biochemical procedure in which yeast converts sugar into ethanol, carbon dioxide, and other metabolic by-products. 

Acetic acid Fermentation

The fermentation of acetic acid is a highly exothermic process that raises the temperature to around 50°C. Only 2% to 4% of lactate is transformed into acetate. A portion of lactate is converted into acetoin while another portion undergoes TCA cycle oxidation. 

Butyric acid Fermentation

Butyric acid fermentation able to oxidise sugar and occasionally amylose and pectin to pyruvate. It is done by anaerobic bacteria which mainly belong to the genus Clostridium. 

Advantages of Fermentation 

Fermentation is the oldest metabolic process and it used in both eukaryotes and prokaryotes. It is used in many industries, and the products formed are:

  • Wine 
  • Biofuels 
  • Yoghurt 
  • Pickles 
  • Sour foods containing lactic acid 
  • Beer 
  • Bread
  • Certain antibiotics and vitamins 

Learning Outcomes

  • Students understands about fermentation.
  • Students understand the fields in which the fermentation works.  
  • Students can know about the products which are fermented in their day-to-day life.