Explain single cell protein $(SCP)$.

(N/A) Conventional agricultural production of cereals,pulses,vegetables,and fruits may not be able to meet the food demand at the rate at which human and animal populations are increasing.
The shift from grain-based to meat-based diets also creates more demand for cereals,as it takes $3-10 \ kg$ of grain to produce $1 \ kg$ of meat through animal farming.
$\Rightarrow$ More than $25\%$ of the human population suffers from hunger and malnutrition.
$\Rightarrow$ One of the alternate sources of protein for animal and human nutrition is Single Cell Protein $(SCP)$.
$\Rightarrow$ Microbes are being grown on an industrial scale as a source of high-quality protein.
$\Rightarrow$ Blue-green algae like $Spirulina$ can be grown easily on materials like wastewater from potato processing plants (containing starch),straw,molasses,animal manure,and even sewage. This produces large quantities of biomass that serve as food rich in protein,minerals,fats,carbohydrates,and vitamins. Incidentally,such utilization also reduces environmental pollution.
Certain bacterial species,like $Methylophilus \ methylotrophus$,because of their high rate of biomass production and growth,can produce $25$ tonnes of protein.
Additionally,edible mushrooms are consumed by many people,and large-scale mushroom culture is a growing industry.