This document discusses different methods of fermentation. It describes solid state fermentation (SSF) where microorganisms are grown on a solid substrate in the absence of free water. SSF is used in industries like food, pharmaceuticals and is more cost effective with less pollution than submerged fermentation. Submerged fermentation grows microorganisms in liquid nutrient media in bioreactors and allows for better heat and mass transfer but is more complex and expensive. The key differences between SSF and submerged fermentation are that SSF uses insoluble substrates with higher water content and inoculum ratio, while submerged fermentation uses soluble substrates, evenly distributed nutrients and a lower water content and inoculum ratio.

1. METHODS OF FERMETATION
BY
G.ARJUN
II M.Sc.Applied Microbiology
Sacred Heart College (Autonomous)
Tirupattur.
TO
Dr. P. SARANRAJ
Head of Department of Microbiology
Sacred Heart College (Autonomous)
Tirupattur.

2. FERMENTATION
Fermentation is a metabolic process that produces chemical changes in
organic substrates through the action of enzymes. In biochemistry, it is
narrowly defined as the extraction of energy from carbohydrates in the
absence of oxygen

3. METHODS OF FERMENTATION
1. Solid state fermentation (SSF)
2. Submerged fermentation (SmF)

4. Solid state fermentation has been defined as “the fermentation process
occurring in the absence or near absence of free water utilizing the solid
substrate”.
It is a biomolecule manufacturing process used in the food,
pharmaceutical, cosmetic, fuel and textile industries. These biomolecules
are mostly metabolites generated by microorganisms grown on a solid
support selected for this purpose.
This technology for the culture of microorganisms is an alternative to
liquid or submerged fermentation, used predominantly for industrial
purposes
SOLID STATE FERMENTATION

5.  Simple and cost effective
 Less effluent release, reduce pollution
 aeration is easy
 Resembles the natural habitat of some fungi and
bacteria
 SSF utilizs solid substrate, thus nutrient rich waste
materials can be easily recycled as substrate
ADVANTAGES

6. SUBMERGED FERMENTATION
Submerged fermentation is a method of cultivating microorganisms in
liquid nutrient media. For industrial production, this implies growing the
selected microorganism in closed vessels, called bioreactors, which contain
nutrient broths.

7. ADVANTAGES OF SUBMERGED FERMENTATION
• Better heat and mass transfer can be achieved
• Better diffusion of microorganisms
• Commercially available in large scale
• Complex in operation, low yeild

8. DISADVANTAGES OF SUBMERGED FERMENTATION
• Expensive due to high cost of required media.
• Low volumetric productivity.
• More efflux is generated.
• Oxygen circulation is not so effective.

9. SOliD STATE FERMENTATION SUBMERGED FERMENATION
Cultivation of microorganisms on soild
state
Cultivation of microorganisms on liquid
state.
Inoculum ratio is high Inoculum ratio is low
Nutrient distribution is not even Nutrient distribution is evenly distributed
Water content of the medium 40-80% Water content of the medium more than
95%
Substrate is insoluble Substrate is soluble
High volume effluent Almost nil effluent
DIFFERENCEBETWEEN SUBMERGED AND SOLID
STATE FERMENTATION