In this article we will discuss about:- 1. Production of SCP 2. Nutritional and Safety Evaluations of SCP 3. Advantages.
The process of SCP production from any microorganism or substrate would have the following basic steps:
1. Provision of a carbon source; it may need physical and/or chemical pre-treatments.
2. Addition, to the carbon source, of sources of nitrogen, phosphorus and other nutrients needed to support optimal growth of the selected microorganism.
3. Prevention of contamination by maintaining sterile or hygienic conditions. The medium components may be heated or sterilized by filtration and fermentation equipment’s may be sterilized.
4. The selected microorganism is inoculated in a pure state.
5. SCP processes are highly aerobic (except those using algae). Therefore, adequate aeration must be provided. In addition, cooling is necessary as considerable heat is generated.
6. The microbial biomass is recovered from the medium.
7. Processing of the biomass for enhancing its usefulness and/or storability.
Biomass production is ordinarily carried out in the continuous mode to maximise yields and economic returns.
Nutritional and Safety Evaluations of SCP:
1. The SCP chemical composition must be characterised in terms of protein, amino acid, nucleic acid, lipid, vitamin, etc. contents.
2. Analysis of substrate residues and toxic substances, e.g., heavy metals, mycotoxins, polycyclic hydrocarbons, etc. must be done.
3. Physical properties like density, particle size, texture, colour, storage, etc. properties should be determined.
4. Microbiological description, e.g., species, strain, should be provided, and information on contamination be also given.
5. The nutritional value should be evaluated on the target species, and other species should also be included. The products for human use will, of necessity, be evaluated over a longer period using a multistaged process.
6. Possible toxic or carcinogenic compounds must be assayed for. These compounds may have been present in the substrate, may be synthesized by the organism or produced during the processing of SCP.
Advantages of SCP:
The SCP processes and products offer several advantages as listed below:
1. The SCP is rich in high quality protein and is rather poor in fats, which is rather desirable (Table 37.4).
2. They can be produced all the year round and are not dependent of the climate (except the algal processes).
3. The microbes are very fast growing and produce large quantities of SCP from relatively very small area of land.
4. They use low cost substrates and, in some cases, such substrates which are being wasted and causing pollution to the environment.
5. When the substrate used for SCP process is a source of pollution, SCP production helps reduce pollution.
6. Strains having high biomass yields and a desirable amino acid composition can be easily selected or produced by genetic engineering.
7. Some SCPs are good sources of vitamins, particularly B-group of vitamins, as well, e.g.. yeasts and mushrooms.
8. Mushrooms are considered as delicacy in the human diet.
9. At present, SCP appears to be the only feasible approach to bridge the gap between requirement and supply of proteins.