Fermentation Definition Designing & constructing
Fermentation is a vessel for the growth of microorganisms which while not permitting contamination and enables the provision of conditions necessary for the maximal production of desire products. The fermenter is also called a bio-fermenter. The main function of a fermenter is to provide a controlled environment for the growth of microorganisms or animal cells to obtain the desired product.
Designing & constructing fermenter:-
Following points must be considered while designing & constructing the fermenter as follows;
- The vessel should be capable of being operated aseptically for no of days & should be reliable for long term operation & meet the requirement of containment
- Adequate aeration & agitation should be provided to meet the metabolic requirement of microorganisms, however, mixing should not cause damage to the organism.
- Power consumption should be as low as possible.
- A system of temperature control should be provided.
- A system of pH control should be provided.
- Sampling facilities should be provided.
- The vessel should be designed to required minimal use of labor in operation, harvesting, cleaning & maintenance.
- Evaporation losses from the fermenter should not be excessive.
- The vessel should be constructed to ensure a smooth internal surface using wells.
- The vessel should be of similar geometry to both smaller & larger vessels in the pilot plant or plant to scale up.
- The cheapest material which enables the satisfactory result to be achieved should be used to cost-effective.
- There should be adequate service provision for individual plants.
Fermentation A Metabolic Process
Functions of various parts of fermenter:-
- Baffles: Prevent vortex and improve aeration efficiency.
- Impeller: Agitator requires d to achieve the number of mixing objectives.
- Sparger: Device which introduced air into the liquid in a fermenter.
Also, Check Helpful Notes Paper
Inoculum development:-
The process of production of inoculum is called inoculum development. The culture used to inoculate in fermentation must be in a healthy active state thus minimizing the length of the lag phase in a subsequent fermentation it must be available in large volume to provide an inoculum of optimum size, it must be free of contamination & must retain the product forming capability.
The critical factor for obtaining suitable inoculum is the choice of the culture medium & the suitability of an inoculum medium is determined by a subsequent performance by an inoculum in the production stage. Lincoln (1960) stated that the lag time in fermentation is minimized by growing culture in a final type medium. To reduced lag phase and thus the fermentation time.
Quantity of inoculum normally used 3-10% of medium volume relatively large inoculum volume is used to generate a large volume of biomass in production time, thus increasing in vessel productivity.
Procedure:-
- Master culture is reconstituted & plated on the solid medium approx 10 colonies of typical morphology of high producer are selected and inoculated on to slopes as the sub-master culture. At this stage, the shaker flask may be Inoculated to check the productivity of culture.
- A sub-master culture is used to inoculate shake flask having 250-1000cm3 containing 50-1000 cm3 of the medium which in turn is used in an inoculum for a larger flask for laboratory fermentation which may be then used for inoculating pilot scale fermenter.
- A culture parity check is carried out at each stage to detect contamination as easily as possible.
Also, Check Helpful Notes Paper
Criteria for transfer of inoculum:-
- The most widely used criteria for transfer of vegetative inoculum is biomass and parameters such as dry weight, turbidity, wet weight, residual nutrient concentration & morphological form.
- The most convenient parameter to use as an indicator of inoculum quality & this parameter includes dissolved oxygen, pH, and an effluent gas.
- Use of carbon dioxide production rate as transfer criteria requires analysis of fermenter effluent air.
- It should be emphasized that the amount of biomass transferred was standardized for three fermentation & thus differences in performance is due to the physiological condition.
- Using probe worker develops an automatic inoculum dispenser allowing a preset viable yeast mast to transfer from yeast storage vessel to brewery fermentation.