SSF and SmF Flashcards
Name the 4 types of fermentations, the microorganisms involved and the end product
- alcoholic fermentation, yeast, alcoholic beverages
- lactic acid fermentation, lactic acid bacteria, lactic acid
- acetic acid fermentation, acetic acid bacteria
- alkali fermentation, bacillus sp, amino acids
What bacteria converts pyruvate into lactic acid in soy sauce
aspergillus
what bacteria converts pyruvate into lactic acid in cheese and yogurt
lactobacillus
What yeast converts pyruvate into ethanol and CO2?
saccharomyces
name some monitoring and controlling parts of a fermenter
- pH electrode
- heater pad (heat system)
- O2 sensor
- foam probe
- cold finger (to cool contents after heating)
- pt100 (temp sensor)
What are some beneficial properties of a fermenter?
- oxygen control
- temperature control
- pH value control
- closed pure culture
- low risk of contamination
What is solid state fermentation?
Solid state fermentation (SSF) carried out in the absence of free-flowing liquid (although containing sufficient water to allow microorganism growth), using a nonsoluble material that acts as both a solid support and a source of nutrients
What is submerged fermentation?
Submerged fermentation (SmF) involves growing the selected microorganism in closed vessels, called bioreactors, which contain nutrient broths.
What kind of bioactive compounds have been developed though the use of fermentation?
antibiotics, pigments, antioxidants, antitumor agent, bio-surfactants, bioactive peptides
What are the advantages of SmF over SSF?
SmF:
1. batch or continuos
2. surface area to volume height ratio is less
3.less space required
5. entire fermentation media used
6. agitation is possible
7. controlling parameters is easy
What are the advantages of SSF over SmF?
SSF:
1. If tray get contaminated, loss of tray only
2. Foaming doesn’t occur
3. power consumption is less
Name some raw materials used in SSF
- vegetable and fruit waste
- wheat bran
- rice
- bagasses
- paper pulp
Name some raw materials for SmF
- soluble sugar
- molasses
- fruit and vegetable juices
- sewage water
Why is solid state fermentation preferred?
➢Less effluent release, reduce pollution
➢ Aeration is easy
➢ Resembles the natural habitat of some fungi and bacteria
➢ SSF utilizes solid substrate, thus nutrient-rich waste materials can be easily recycled as substrate
➢ Substrates are used very slowly and steadily so that the same substrate can be used for longer fermentation period
➢ SSF is best suited for fermentation techniques involving fungi and microorganisms that require less moisture content
What are the factors involved in SSF process?
➢ Selection of Micro-organisms
➢ Substrate
➢ Process Optimization
➢ Product Isolation & Purification
Name micro-organisms used in SSF
bacteria, yeast and filamentous fungi
organisms that require less moisture content
What are the applications of SSF?
- production of industrial enzymes
- production of bio pesticides
others: antibiotic, organic acid production
State a major problem in SSF
Heat transfer
heat produced –> substrate has poor thermal conductivity –>heat removal slow –> product denaturation + poor growth of microbe –> lower yield
What kind of organisms is the technique of SmF best suited for?
bacteria that require high moisture.
What is one additional advantage of SmF?
easier product purification
What is a bioreactor?
Bioreactor: device, usually a vessel, used to direct the activity of a biological catalyst to achieve a desired chemical transformation
What is a fermenter?
Fermenter: type of bioreactor in which the biocatalyst is a living cell.
Name some factors that affect the performance of a bioreator?
- nutrient supply
- aeration
- agitation
- sterile condition
- heat removal
