One of the oldest methods of food preservation is fermentation. It has changed, refined, and diversified throughout the centuries. Fermentation has remained an important technology throughout mankind’s history, despite developments in food science and technology giving rise to a wide spectrum of new food technologies. Fermentation is said to provide numerous advantages. It preserves and enriches food, promotes digestion, and improves taste and flavour. Then What is a fermenter?
A Fermenter is a device that is used to carry out the fermentation process utilising microorganisms, which is why it is also known as a “Fermenter or Bioreactor.” It contains all of the components required for the commercial synthesis of compounds such as antibiotics, enzymes, and drinks in a variety of sectors.
The microorganisms in the fermenter are built in such a way that a larger value of the product can be formed with a minimal amount of media. It has a wide range of applications in the food sector, wastewater treatment, and so on. Fermentation is the process of bioprocessing raw substrates using microbial biomass (mostly yeasts and bacteria).
Types of Fermenters
Fermentation systems can be liquid (also called submerged) or solid (also called surface). The majority of fermenters used in industry are types of submerged fermenters, which conserve space and are easier to manage and build.
Submerged fermenters come in a variety of shapes and configurations, and they can be classified as aerated or anaerobic, batch or continuous. Aerated Stirred Tank Batch Fermenters are the most often utilised fermenters. There are five different types of fermenters:
- Stirred tank fermenter
- Airlift fermenter
- Fluidised bed fermenter
- Packed bed fermenter
- Photo fermenter
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Stirred Tank Fermenter
The motor drive shaft and a variable number of impellers make up this component (more than one). The diameter of the impellers is a third of the vessel’s diameter. This bioreactor has a height-to-diameter ratio of around 3:5. A single opening in the tube attached externally allows air to enter the culture media. It makes it possible for the contents to be distributed more evenly throughout the ship. The following are some of its primary functions:
- Homogenisation
- Solid-state suspension
- The medium is aerated
- Change of heat
Rotating stirrer and baffle can be located at the top or bottom of a stirred tank fermenter. It mostly employs a batch fermentation procedure.
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Airlift Fermenter
It is made out of a single container that contains a hollow tube. “Draft tube” is the name for this hollow tube. At the bottom of the fermenter is a gas flow entrance that permits oxygen to pass through. The perforated disc or tube is connected to the gas flow input, allowing air to be distributed continuously.
Mechanical agitation arrangements are not present in this sort of bioreactor. The airlift name suggests that the medium is lifted aloft by the air. Internal liquid circulation channels allow the medium to move continuously. Fermentation takes place at a set volume and circulation rate in this environment.
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Fluidised Bed Fermenter
This bioreactor has a larger top section. The fluid’s velocity is slowed by this expansion. It has a narrow bottom section. It’s made in a way that:
- Inside the vessel, the solid remains.
- And then there’s a flow of liquid out the other end.
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Packed Bed Fermenter
It comprises a cylindrical vessel and a biocatalyst-packed bed. The properties of the solid matrix employed in the packed bed fermenter are as follows:
- Non-porous or porous
- Extremely compressible
- Rigid
A nutrient broth constantly flows over the immobilised biocatalyst in this type of fermenter. Following that, a product is released into the fluid at the bottom of the culture jar, where it can then be retrieved. Fluid can flow upward or downward in this area.
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Photo Fermenter
This fermenter operates on the basis of light energy, which can be achieved through direct sunshine or artificial lighting. It’s utilised to make p-carotene, astaxanthin, and other antioxidants. Glass or plastic make up the majority of this sort of bioreactor. The following components make up a photo fermenter:
- 1 container
- Tubes or panels count
Conclusion
Hence, fermenters is a closed cylindrical tank that supports the biochemical and chemical activity of microorganisms to carry out the conversion of raw materials into usable products. Because it uses microbial biomass to complete the fermentation process, it is also known as a bioreactor. Fermentation procedures are separated into surface and submersion processes depending on the usage of stock culture. Surface fermentation involves growing biomass on the raw substrate’s surface, whereas submersion fermentation involves growing microbes in the raw substrate.