The key difference between fermentation and putrefaction is that fermentation is a metabolic process where microorganisms, especially yeast and bacteria, convert sugar into acids, gasses and alcohols while putrefaction is the decay of organic matter by microorganisms, which results in the formation of compost and a foul smell.
Fermentation and putrefaction are two processes carried out by microorganisms, especially bacteria and fungi. Both processes are anaerobic. They convert complex organic molecules into simpler forms. Fermentation produces desirable products, and it is a controlled process. Putrefaction produces composts and an unpleasant odour, and it is not a controlled process.
CONTENTS
1. Overview and Key Difference
2. What is Fermentation
3. What is Putrefaction
4. Similarities Between Fermentation and Putrefaction
5. Side by Side Comparison – Fermentation and Putrefaction in Tabular Form
6. Summary
What is Fermentation?
Fermentation is an anaerobic process that converts sugar molecules into acids and gasses or alcohols. It is done by fermentative microorganisms such as yeasts and bacteria. Since it is an anaerobic process, it occurs in the absence of molecular oxygen. Fermentation is an industrially important process. Hence, this metabolic process has great use in the industrial production of dairy products, bakery products and alcoholic beverages.
Figure 01: Fermentation
There are two main types of fermentation, both of which require the involvement of enzymes. These two processes are lactic acid fermentation and ethanol fermentation. In lactic acid fermentation, conversion of the pyruvate sugar moiety into lactic acid takes place under the influence of lactic acid dehydrogenase. Lactic acid fermentation primarily occurs in bacteria and in human muscles. The buildup of lactic acid in human muscles leads to the onset of cramps. Ethanol fermentation takes place primarily in plants and in some microbes. The enzymes acetaldehyde decarboxylase and ethanol dehydrogenase facilitate this process.
What is Putrefaction?
Putrefaction is the decomposition of organic matter by the action of microorganisms. It is a type of anaerobic decomposition of organic matter. It is an uncontrollable process. Generally, putrefaction produces a foul smell. Sometimes, putrefaction generates toxic organic compounds as well. Putrefying bacteria and fungi release gasses that can infiltrate and decay organic matter. Putrefaction is the fifth stage of death. Generally, it occurs between 10 to 20 days of the death of an organism. Putrefaction mainly involves decomposition of proteins, breakdown of the tissues, and liquefaction of the organs.
Figure 02: Putrefaction
There are external and internal factors affecting putrefaction. Environmental temperature, moisture and air exposure, and light exposure are several external factors. Age of the dead body, external injuries, condition and the cause of death are several internal factors affecting the putrefaction. The rate of putrefaction is higher in the air than soil and water. Putrefaction can be delayed by certain chemicals including carbolic acid, arsenic, strychnine, and zinc chloride
What are the Similarities Between Fermentation and Putrefaction?
- Fermentation and putrefaction involve the transformation of organic matter into simple molecules.
- Both fermentation and putrefaction are done by microorganisms.
- These processes can produce some unique smells.
- Microbes carry out these two processes in order to obtain their required energy.
- Both processes involve multiple chemical reactions.
What is the Difference Between Fermentation and Putrefaction?
Fermentation is an anaerobic microbial process that converts sugars into acids, gases and alcohols. Putrefaction is an anaerobic process that decomposes dead plant and animal matter. So, this is the key difference between fermentation and putrefaction. Moreover, fermentation is a controlled process, while putrefaction is an uncontrolled process.
Application wise, fermentation is industrially important when producing dairy products, bakery products and alcoholic beverages while putrefaction is important in the decomposing and recycling matter in nature.
Below infographic sums up the differences between fermentation and putrefaction in tabular form.
Summary – Fermentation vs Putrefaction
Both fermentation and putrefaction are microbial processes that occur anaerobically. Complex organic matter is converted into simpler building blocks by both processes. Fermentation is a controlled process, while putrefaction is an uncontrollable process. Moreover, putrefaction produces a characteristic foul odour, unlike fermentation. Thus, this summarizes the difference between fermentation and putrefaction.
Reference:
1. “Fermentation.” Wikipedia, Wikimedia Foundation, 18 Oct. 2020, Available here.
2. “Putrefaction.” Farlex, Available here.
Image Courtesy:
1. “Ethanol fermentation-1” By Davidcarmack – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Putrefaction” By gerogeri (CC BY-NC-ND 2.0) via Flickr