BOTANY Higher Secondary Second Year - Textbooks Online

The term ‘single cell protein’ was coined in 1966. The dried cells of
microorganisms used as food or feed for animals and they are collectively
known as Microbial proteins. This term was replaced by a new term
‘single cell protein’. The isolated protein or the total cell material is
called the SCP.
In view of the insufficient world food supply and the high protein
content of microbial cells, the use of biomass produced in the fermentor
(special sterilized vessel) or bio-reactor would be ideal supplement for
conventional food. Single cell protein is of great nutritional value because
of its high protein, vitamin and lipid content and for its essential amino
acids. In many countries, however people hesitate to use SCP as a major
food source because of the following -
The high nucleic acid content (4 to 6 per cent in algae, 6 to10 per cent
in yeast of SCP) can cause health problems like uric acid formation,
kidney stones and rheumatism in human beings.
Toxic or carcinogenic (cancer causing) substances absorbed from the
microbial growth substrate may be present.
Slow digestion of microbial cell in the digestive tract may cause
vomiting, indigestion and allergic reaction.
High cost of production will also be a deciding factor in determining
the ultimate place of SCP in the human or animal diet.
The following substrates are being studied for SCP production:
alkanes, methane, methanol, cellulose, carbohydrates and waste
materials.
Natural sources like wood chips, rice husk, cane and beet molasses,
peas and coffee industrial waste from which cellulose is obtained and
are used for the production of SCP.
Large scale cultivation of yeast on molasses is widely used in the
manufacture of Baker’s yeast containing mycoproteins which is used
in the SCP production.
Domestic sewage is not suitable for large scale SCP production. But
it is more important for methane production. The industrial wastewater
from cellulose processing, coffee and starch production, and food
processing have been used for SCP production.
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